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[10-Q] Alliant Energy Corporation Quarterly Earnings Report

Filing Impact
(Moderate)
Filing Sentiment
(Neutral)
Form Type
10-Q
Rhea-AI Filing Summary

Alliant Energy 10-Q (Q2 2025)

For the three months ended June 30, 2025 Alliant Energy reported consolidated revenues of $961 million versus $894 million a year ago and operating income of $223 million versus $130 million. Net income attributable to common shareowners was $174 million compared with $87 million; diluted EPS was $0.68 versus $0.34. For the six months, revenues were $2,088 million versus $1,925 million and net income was $387 million versus $245 million (diluted EPS $1.50 versus $0.95).

Key balance sheet and cash flow items: cash and equivalents increased to $329 million from $81 million and total assets were $23,750 million. Long-term debt, net (excluding current portion) rose to $9,642 million from $8,677 million and current maturities increased to $1,373 million. Six-month construction and acquisition expenditures totaled $976 million. Net cash from operating activities was $492 million, while net cash used for investing activities was $894 million.

Alliant Energy 10-Q (Q2 2025)

Per i tre mesi chiusi il 30 giugno 2025 Alliant Energy ha riportato ricavi consolidati di $961 milioni rispetto a $894 milioni dell'anno precedente e un reddito operativo di $223 milioni rispetto a $130 milioni. L'utile netto attribuibile agli azionisti ordinari è stato di $174 milioni rispetto a $87 milioni; l'EPS diluito è stato di $0.68 contro $0.34. Nei sei mesi, i ricavi sono stati di $2,088 milioni rispetto a $1,925 milioni e l'utile netto è stato di $387 milioni rispetto a $245 milioni (EPS diluito $1.50 vs $0.95).

Elementi chiave di stato patrimoniale e flussi di cassa: la liquidità e gli equivalenti sono saliti a $329 milioni da $81 milioni e il totale degli attivi è risultato pari a $23,750 milioni. Il debito a lungo termine netto (esclusa la quota a breve termine) è aumentato a $9,642 milioni da $8,677 milioni e le scadenze correnti sono salite a $1,373 milioni. Le spese per costruzioni e acquisizioni nei sei mesi sono state di $976 milioni. Il flusso di cassa netto dalle attività operative è stato di $492 milioni, mentre il flusso di cassa netto utilizzato per attività di investimento è stato di $894 milioni.

Alliant Energy 10-Q (Q2 2025)

Para los tres meses finalizados el 30 de junio de 2025, Alliant Energy informó ingresos consolidados de $961 millones frente a $894 millones del año anterior y un resultado operativo de $223 millones frente a $130 millones. El beneficio neto atribuible a los accionistas ordinarios fue de $174 millones comparado con $87 millones; las ganancias diluidas por acción (EPS) fueron de $0.68 frente a $0.34. En el semestre, los ingresos fueron de $2,088 millones frente a $1,925 millones y el beneficio neto fue de $387 millones frente a $245 millones (EPS diluido $1.50 vs $0.95).

Aspectos clave del balance y flujos de efectivo: el efectivo y equivalentes aumentaron a $329 millones desde $81 millones y el total de activos fue de $23,750 millones. La deuda a largo plazo neta (excluyendo la porción corriente) subió a $9,642 millones desde $8,677 millones y las maturidades corrientes aumentaron a $1,373 millones. Las inversiones en construcción y adquisiciones en seis meses totalizaron $976 millones. El efectivo neto procedente de actividades operativas fue de $492 millones, mientras que el efectivo neto usado en actividades de inversión fue de $894 millones.

Alliant Energy 10-Q (Q2 2025)

2025년 6월 30일로 끝나는 3개월 동안 Alliant Energy는 연결 매출액이 $961 million으로 전년 동기 $894 million 대비 증가했고, 영업이익은 $223 million으로 전년의 $130 million에서 늘었습니다. 보통주주에게 귀속되는 순이익은 $174 million으로 전년의 $87 million에서 증가했으며 희석 주당순이익(EPS)은 $0.68로 전년의 $0.34에 비해 높았습니다. 반기 기준으로는 매출액이 $2,088 million$1,925 million, 순이익은 $387 million$245 million이었고(희석 EPS $1.50 vs $0.95).

대차대조표 및 현금흐름의 주요 항목: 현금 및 현금성자산은 $81 million에서 $329 million으로 증가했으며 총자산은 $23,750 million이었습니다. 단기분을 제외한 장기순부채는 $8,677 million에서 $9,642 million으로 상승했고 단기 만기는 $1,373 million으로 늘었습니다. 6개월간 건설 및 인수 지출은 총 $976 million이었고, 영업활동으로 인한 순현금은 $492 million, 투자활동으로 사용된 순현금은 $894 million이었습니다.

Alliant Energy 10-Q (Q2 2025)

Pour les trois mois clos le 30 juin 2025, Alliant Energy a déclaré un chiffre d'affaires consolidé de $961 millions contre $894 millions un an plus tôt et un résultat d'exploitation de $223 millions contre $130 millions. Le résultat net attribuable aux détenteurs d'actions ordinaires s'est élevé à $174 millions contre $87 millions ; le bénéfice dilué par action (EPS) était de $0.68 contre $0.34. Sur six mois, le chiffre d'affaires s'établissait à $2,088 millions contre $1,925 millions et le résultat net à $387 millions contre $245 millions (EPS dilué $1.50 vs $0.95).

Principaux postes du bilan et des flux de trésorerie : les liquidités et équivalents de trésorerie ont augmenté à $329 millions contre $81 millions et le total des actifs était de $23,750 millions. La dette à long terme nette (hors partie à court terme) est passée à $9,642 millions contre $8,677 millions et les échéances courantes ont augmenté à $1,373 millions. Les dépenses de construction et d'acquisition sur six mois se sont élevées à $976 millions. Les flux de trésorerie nets provenant des activités opérationnelles se sont élevés à $492 millions, tandis que les flux nets utilisés pour les activités d'investissement se sont élevés à $894 millions.

Alliant Energy 10-Q (Q2 2025)

Für die drei Monate zum 30. Juni 2025 meldete Alliant Energy konsolidierte Umsatzerlöse von $961 Millionen gegenüber $894 Millionen im Vorjahr und ein Betriebsergebnis von $223 Millionen gegenüber $130 Millionen. Der auf Inhaber von Stammaktien entfallende Nettogewinn belief sich auf $174 Millionen gegenüber $87 Millionen; das verwässerte Ergebnis je Aktie (EPS) lag bei $0.68 gegenüber $0.34. Für die sechs Monate beliefen sich die Umsatzerlöse auf $2,088 Millionen gegenüber $1,925 Millionen und der Nettogewinn auf $387 Millionen gegenüber $245 Millionen (verwässertes EPS $1.50 vs. $0.95).

Wesentliche Bilanz- und Cashflow-Positionen: Zahlungsmittel und Zahlungsmitteläquivalente stiegen auf $329 Millionen von $81 Millionen und die Bilanzsumme belief sich auf $23,750 Millionen. Langfristige Schulden netto (ohne kurzfristigen Anteil) erhöhten sich auf $9,642 Millionen von $8,677 Millionen und die kurzfristigen Fälligkeiten stiegen auf $1,373 Millionen. Die Bau- und Akquisitionsausgaben für sechs Monate beliefen sich auf $976 Millionen. Der Netto-Cashflow aus operativer Geschäftstätigkeit betrug $492 Millionen, während der Netto-Cashflow aus Investitionstätigkeit $894 Millionen betrug.

Positive
  • Revenue growth: Consolidated revenues increased to $961M in Q2 2025 from $894M in Q2 2024
  • Improved profitability: Operating income rose to $223M (Q2 2025) from $130M, and net income attributable to common shareowners increased to $174M from $87M
  • EPS expansion: Diluted EPS improved to $0.68 in Q2 2025 from $0.34 a year ago
  • Higher liquidity position: Cash and cash equivalents increased to $329M at June 30, 2025 from $81M at December 31, 2024
Negative
  • Rising leverage: Long-term debt, net (ex current portion) increased to $9,642M from $8,677M at year-end 2024
  • Large near-term maturities: Current maturities of long-term debt increased to $1,373M
  • Operating cash flow contraction: Net cash from operating activities declined to $492M for six months in 2025 from $562M in 2024
  • Increased accounts receivable: Consolidated accounts receivable rose to $518M from $427M, pressuring working capital
  • Higher interest expense: Interest expense increased to $124M in Q2 2025 from $108M in Q2 2024

Insights

TL;DR: Strong revenue and earnings growth led to higher EPS, but heavy capex and rising debt raise near-term funding needs.

Alliant Energy delivered notable top-line and profitability improvements in Q2 2025: consolidated revenues increased to $961M and operating income nearly doubled year-over-year to $223M, driving net income of $174M and diluted EPS of $0.68. The six-month results reinforce the trend with net income of $387M. Investment activity is high: utility construction and acquisition expenditures of $976M for six months and net cash used for investing of $894M. Management financed growth with incremental long-term debt (net long-term debt up to $9,642M) and current maturities of $1,373M, while operating cash flow declined to $492M. Investors should weigh improved operating performance and EPS against increased leverage and substantial ongoing capex requirements.

TL;DR: Operational results improved, but increased receivables, higher interest expense and growing near-term debt maturities raise liquidity and regulatory recovery risk.

From a risk perspective, Alliant shows stronger earnings but several metrics warrant monitoring. Accounts receivable grew (consolidated AR $518M versus $427M at year-end), and net cash from operations fell to $492M from $562M, increasing reliance on financing. Interest expense rose (Q2 interest expense $124M versus $108M), and long-term debt increased to $9,642M with current maturities of $1,373M. The company continues substantial capex, evidenced by $976M of utility construction spend in six months. Regulatory recovery items and prior period asset valuation impacts (Lansing charge in 2024) underscore regulatory dependency. Overall impact: mixed; improved earnings reduce near-term earnings risk but leverage and cash flow trends elevate liquidity and regulatory execution risk.

Alliant Energy 10-Q (Q2 2025)

Per i tre mesi chiusi il 30 giugno 2025 Alliant Energy ha riportato ricavi consolidati di $961 milioni rispetto a $894 milioni dell'anno precedente e un reddito operativo di $223 milioni rispetto a $130 milioni. L'utile netto attribuibile agli azionisti ordinari è stato di $174 milioni rispetto a $87 milioni; l'EPS diluito è stato di $0.68 contro $0.34. Nei sei mesi, i ricavi sono stati di $2,088 milioni rispetto a $1,925 milioni e l'utile netto è stato di $387 milioni rispetto a $245 milioni (EPS diluito $1.50 vs $0.95).

Elementi chiave di stato patrimoniale e flussi di cassa: la liquidità e gli equivalenti sono saliti a $329 milioni da $81 milioni e il totale degli attivi è risultato pari a $23,750 milioni. Il debito a lungo termine netto (esclusa la quota a breve termine) è aumentato a $9,642 milioni da $8,677 milioni e le scadenze correnti sono salite a $1,373 milioni. Le spese per costruzioni e acquisizioni nei sei mesi sono state di $976 milioni. Il flusso di cassa netto dalle attività operative è stato di $492 milioni, mentre il flusso di cassa netto utilizzato per attività di investimento è stato di $894 milioni.

Alliant Energy 10-Q (Q2 2025)

Para los tres meses finalizados el 30 de junio de 2025, Alliant Energy informó ingresos consolidados de $961 millones frente a $894 millones del año anterior y un resultado operativo de $223 millones frente a $130 millones. El beneficio neto atribuible a los accionistas ordinarios fue de $174 millones comparado con $87 millones; las ganancias diluidas por acción (EPS) fueron de $0.68 frente a $0.34. En el semestre, los ingresos fueron de $2,088 millones frente a $1,925 millones y el beneficio neto fue de $387 millones frente a $245 millones (EPS diluido $1.50 vs $0.95).

Aspectos clave del balance y flujos de efectivo: el efectivo y equivalentes aumentaron a $329 millones desde $81 millones y el total de activos fue de $23,750 millones. La deuda a largo plazo neta (excluyendo la porción corriente) subió a $9,642 millones desde $8,677 millones y las maturidades corrientes aumentaron a $1,373 millones. Las inversiones en construcción y adquisiciones en seis meses totalizaron $976 millones. El efectivo neto procedente de actividades operativas fue de $492 millones, mientras que el efectivo neto usado en actividades de inversión fue de $894 millones.

Alliant Energy 10-Q (Q2 2025)

2025년 6월 30일로 끝나는 3개월 동안 Alliant Energy는 연결 매출액이 $961 million으로 전년 동기 $894 million 대비 증가했고, 영업이익은 $223 million으로 전년의 $130 million에서 늘었습니다. 보통주주에게 귀속되는 순이익은 $174 million으로 전년의 $87 million에서 증가했으며 희석 주당순이익(EPS)은 $0.68로 전년의 $0.34에 비해 높았습니다. 반기 기준으로는 매출액이 $2,088 million$1,925 million, 순이익은 $387 million$245 million이었고(희석 EPS $1.50 vs $0.95).

대차대조표 및 현금흐름의 주요 항목: 현금 및 현금성자산은 $81 million에서 $329 million으로 증가했으며 총자산은 $23,750 million이었습니다. 단기분을 제외한 장기순부채는 $8,677 million에서 $9,642 million으로 상승했고 단기 만기는 $1,373 million으로 늘었습니다. 6개월간 건설 및 인수 지출은 총 $976 million이었고, 영업활동으로 인한 순현금은 $492 million, 투자활동으로 사용된 순현금은 $894 million이었습니다.

Alliant Energy 10-Q (Q2 2025)

Pour les trois mois clos le 30 juin 2025, Alliant Energy a déclaré un chiffre d'affaires consolidé de $961 millions contre $894 millions un an plus tôt et un résultat d'exploitation de $223 millions contre $130 millions. Le résultat net attribuable aux détenteurs d'actions ordinaires s'est élevé à $174 millions contre $87 millions ; le bénéfice dilué par action (EPS) était de $0.68 contre $0.34. Sur six mois, le chiffre d'affaires s'établissait à $2,088 millions contre $1,925 millions et le résultat net à $387 millions contre $245 millions (EPS dilué $1.50 vs $0.95).

Principaux postes du bilan et des flux de trésorerie : les liquidités et équivalents de trésorerie ont augmenté à $329 millions contre $81 millions et le total des actifs était de $23,750 millions. La dette à long terme nette (hors partie à court terme) est passée à $9,642 millions contre $8,677 millions et les échéances courantes ont augmenté à $1,373 millions. Les dépenses de construction et d'acquisition sur six mois se sont élevées à $976 millions. Les flux de trésorerie nets provenant des activités opérationnelles se sont élevés à $492 millions, tandis que les flux nets utilisés pour les activités d'investissement se sont élevés à $894 millions.

Alliant Energy 10-Q (Q2 2025)

Für die drei Monate zum 30. Juni 2025 meldete Alliant Energy konsolidierte Umsatzerlöse von $961 Millionen gegenüber $894 Millionen im Vorjahr und ein Betriebsergebnis von $223 Millionen gegenüber $130 Millionen. Der auf Inhaber von Stammaktien entfallende Nettogewinn belief sich auf $174 Millionen gegenüber $87 Millionen; das verwässerte Ergebnis je Aktie (EPS) lag bei $0.68 gegenüber $0.34. Für die sechs Monate beliefen sich die Umsatzerlöse auf $2,088 Millionen gegenüber $1,925 Millionen und der Nettogewinn auf $387 Millionen gegenüber $245 Millionen (verwässertes EPS $1.50 vs. $0.95).

Wesentliche Bilanz- und Cashflow-Positionen: Zahlungsmittel und Zahlungsmitteläquivalente stiegen auf $329 Millionen von $81 Millionen und die Bilanzsumme belief sich auf $23,750 Millionen. Langfristige Schulden netto (ohne kurzfristigen Anteil) erhöhten sich auf $9,642 Millionen von $8,677 Millionen und die kurzfristigen Fälligkeiten stiegen auf $1,373 Millionen. Die Bau- und Akquisitionsausgaben für sechs Monate beliefen sich auf $976 Millionen. Der Netto-Cashflow aus operativer Geschäftstätigkeit betrug $492 Millionen, während der Netto-Cashflow aus Investitionstätigkeit $894 Millionen betrug.

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Table of Contents                        
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 10-Q
    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended June 30, 2025

or

    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from                    to                    

alliantenergylogo.jpg

Name of Registrant, State of Incorporation, Address of Principal Executive Offices, Telephone Number, Commission File Number, IRS Employer Identification Number

ALLIANT ENERGY CORPORATION
(a Wisconsin Corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311
Commission File Number - 1-9894
IRS Employer Identification Number - 39-1380265

INTERSTATE POWER & LIGHT COMPANY
(an Iowa corporation)
Alliant Energy Tower
Cedar Rapids, Iowa 52401
Telephone (319) 786-4411
Commission File Number - 1-4117
IRS Employer Identification Number - 42-0331370

WISCONSIN POWER & LIGHT COMPANY
(a Wisconsin corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311
Commission File Number - 0-337
IRS Employer Identification Number - 39-0714890
This combined Form 10-Q is separately filed by Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company. Information contained in the Form 10-Q relating to Interstate Power and Light Company and Wisconsin Power and Light Company is filed by each such registrant on its own behalf. Each of Interstate Power and Light Company and Wisconsin Power and Light Company makes no representation as to information relating to registrants other than itself.

Securities registered pursuant to Section 12(b) of the Act:
Alliant Energy Corporation, Common Stock, $0.01 Par Value, Trading Symbol LNT, Nasdaq Global Select Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.
Alliant Energy Corporation - Yes ☒ No ☐
Interstate Power and Light Company - Yes ☒ No ☐
Wisconsin Power and Light Company - Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).
Alliant Energy Corporation - Yes ☒ No ☐
Interstate Power and Light Company - Yes ☒ No ☐
Wisconsin Power and Light Company - Yes ☒ No ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Alliant Energy Corporation - Large Accelerated Filer ☒ Accelerated Filer ☐ Non-accelerated Filer ☐ Smaller Reporting Company Emerging Growth Company
Interstate Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company Emerging Growth Company
Wisconsin Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company Emerging Growth Company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
Alliant Energy Corporation ☐
Interstate Power and Light Company ☐
Wisconsin Power and Light Company ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).
Alliant Energy Corporation - Yes No ☒
Interstate Power and Light Company - Yes No ☒
Wisconsin Power and Light Company - Yes No ☒
Number of shares outstanding of each class of common stock as of June 30, 2025:
Alliant Energy Corporation, Common Stock, $0.01 par value, 256,969,227 shares outstanding
Interstate Power and Light Company, Common Stock, $2.50 par value, 13,370,788 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)
Wisconsin Power and Light Company, Common Stock, $5 par value, 13,236,601 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)



Table of Contents                        
TABLE OF CONTENTS
Page
Definitions
Forward-looking Statements
1
Part I. Financial Information
3
Item 1. Condensed Consolidated Financial Statements (Unaudited)
3
Alliant Energy Corporation
3
Interstate Power and Light Company
6
Wisconsin Power and Light Company
9
Combined Notes to Condensed Consolidated Financial Statements
12
1. Summary of Significant Accounting Policies
12
2. Regulatory Matters
12
3. Receivables
13
4. Investments
13
5. Common Equity
14
6. Debt
16
7. Revenues
18
8. Income Taxes
19
9. Benefit Plans
19
10. Derivative Instruments
20
11. Fair Value Measurements
21
12. Commitments and Contingencies
23
13. Segments of Business
25
14. Related Parties
27
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations
28
Item 3. Quantitative and Qualitative Disclosures About Market Risk
36
Item 4. Controls and Procedures
36
Part II. Other Information
37
Item 1. Legal Proceedings
37
Item 1A. Risk Factors
37
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds
37
Item 5. Other Information
37
Item 6. Exhibits
38
Signatures
38

DEFINITIONS
The following abbreviations or acronyms used in this report are defined below:
Abbreviation or AcronymDefinitionAbbreviation or AcronymDefinition
2024 Form 10-K
Combined Annual Report on Form 10-K filed by Alliant Energy, IPL and WPL for the year ended Dec. 31, 2024
IPLInterstate Power and Light Company
AEFAlliant Energy Finance, LLCIUCIowa Utilities Commission
Alliant EnergyAlliant Energy CorporationMDAManagement’s Discussion and Analysis of Financial Condition and Results of Operations
ATCAmerican Transmission Company LLCMISOMidcontinent Independent System Operator, Inc.
ATC HoldingsInterest in American Transmission Company LLC and ATC Holdco LLCMWMegawatt
Corporate ServicesAlliant Energy Corporate Services, Inc.MWhMegawatt-hour
DthDekathermN/ANot applicable
EGUElectric generating unitNote(s)Combined Notes to Condensed Consolidated Financial Statements
EPAU.S. Environmental Protection AgencyOPEBOther postretirement benefits
EPSEarnings per weighted average common sharePSCWPublic Service Commission of Wisconsin
Financial StatementsCondensed Consolidated Financial StatementsU.S.United States of America
FTRFinancial transmission rightWest RiversideWest Riverside Energy Center and Solar Facility
GAAPU.S. generally accepted accounting principlesWPLWisconsin Power and Light Company


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FORWARD-LOOKING STATEMENTS
Statements contained in this report that are not of historical fact are forward-looking statements intended to qualify for the safe harbors from liability established by the Private Securities Litigation Reform Act of 1995. These forward-looking statements can be identified as such because the statements include words such as “may,” “believe,” “expect,” “anticipate,” “plan,” “project,” “will,” “projections,” “estimate,” or other words of similar import. Similarly, statements that describe future financial performance or plans or strategies are forward-looking statements. Such forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those expressed in, or implied by, such statements. Some, but not all, of the risks and uncertainties of Alliant Energy, IPL and WPL that could materially affect actual results include:
IPL’s and WPL’s ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of and/or the return on costs, including fuel costs, operating costs, transmission costs, capacity costs, costs of generation projects including such costs that are incurred prior to regulatory approval or exceed initial estimates, deferred expenditures, deferred tax assets, tax expense, interest expense, capital expenditures, marginal costs to service new customers, and remaining costs related to EGUs that have been or may be permanently closed and certain other retired assets, environmental remediation costs, and decreases in sales volumes, as well as earning their authorized rates of return, payments to their parent of expected levels of dividends, the impact of rate design on current and potential customers and demand for energy in their service territories, and the ability to obtain regulatory approval with acceptable conditions for individual customer rates for large load growth customers;
the impact of IPL’s retail electric base rate moratorium;
the ability to complete construction of generation and energy storage projects by planned in-service dates and within the cost targets set by regulators due to cost increases of and access to materials, equipment and commodities, which could result from tariffs, duties or other assessments, inflation, labor issues or supply shortages, the ability to successfully resolve warranty issues or contract disputes and the ability to obtain adequate generator interconnection agreements to connect the new projects to MISO in a timely manner;
weather effects on utility sales volumes and operations;
the direct or indirect effects resulting from cybersecurity incidents or attacks on Alliant Energy, IPL, WPL, or their suppliers, contractors and partners, or responses to such incidents;
the impact of customer- and third party-owned generation, including alternative electric suppliers, in IPL’s and WPL’s service territories on system reliability, operating expenses and customers’ demand for electricity;
economic conditions and the impact of business or facility closures in IPL’s and WPL’s service territories;
the ability and cost to provide sufficient generation and the ability of ITC Midwest LLC and ATC to provide sufficient transmission capacity for potential load growth, including significant new commercial or industrial customers, such as data centers;
the ability of potential large load growth customers to timely construct new facilities, as well as the resulting higher system load demand by expected levels and timeframes;
the impact of energy efficiency, franchise retention and customer disconnects on sales volumes and operating income;
the impact that price changes may have on IPL’s and WPL’s customers’ demand for electric and gas services and their ability to pay their bills;
changes in the price of delivered natural gas, transmission, purchased electric energy, purchased electric capacity and delivered coal, particularly during elevated market prices, and any resulting changes to counterparty credit risk, due to shifts in supply and demand caused by market conditions, regulations and MISO’s seasonal resource adequacy process;
the ability to obtain regulatory approval for construction projects with acceptable conditions;
the ability to achieve the expected level of tax benefits for renewable generation and energy storage projects based on tax guidelines, timely beginning of construction and in-service dates, sourcing permissible amounts of construction support from entities with ties to certain foreign countries, compliance with prevailing wage and apprenticeship requirements, project costs and the level of electricity output generated by qualifying generating facilities, and the ability to efficiently utilize the renewable generation and energy storage project tax benefits to achieve IPL’s authorized rate of return and for the benefit of IPL’s and WPL’s customers;
federal and state regulatory or governmental actions, including the impact of legislation, Treasury regulations, executive orders, interpretations and guidance, and changes in public policy, including changes impacting renewable tax credits;
the ability to utilize tax credits generated to date, and those that may be generated in the future, before they expire, as well as the ability to transfer tax credits that may be generated in the future at adequate pricing;
the impacts of changes in the tax code, including tax rates, minimum tax rates, adjustments made to deferred tax assets and liabilities, and changes impacting the availability of and ability to transfer renewable tax credits, including preserving the qualification of any future tax credits;
disruptions to ongoing operations and the supply of materials, services, equipment and commodities needed to continue to operate and maintain existing assets and to construct capital projects, which may result from geopolitical issues, tariffs, supplier manufacturing constraints, regulatory requirements, labor issues or transportation issues, and thus affect the ability to meet capacity requirements and result in increased capacity expense;
inflation and higher interest rates;
continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;
the future development of technologies related to electrification, and the ability to reliably store and manage electricity;
employee workforce factors, including the ability to hire and retain employees with specialized skills, impacts from employee retirements, changes in key executives, ability to create desired corporate culture, collective bargaining agreements and negotiations, work stoppages or restructurings;
disruptions in the supply and delivery of natural gas, purchased electricity and coal;
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changes to the creditworthiness of, or performance of obligations by, counterparties with which Alliant Energy, IPL and WPL have contractual arrangements, including large load growth customers, participants in the energy markets and fuel suppliers and transporters;
the impact of penalties or third-party claims related to, or in connection with, a failure to maintain the security of personally identifiable information, including associated costs to notify affected persons and to mitigate their information security concerns;
impacts that terrorist attacks may have on Alliant Energy’s, IPL’s and WPL’s operations and recovery of costs associated with restoration activities, or on the operations of Alliant Energy’s investments;
changes to MISO’s resource adequacy process establishing capacity planning reserve margin and capacity accreditation requirements that may impact how and when new and existing generating facilities, including IPL’s and WPL’s additional solar generation, may be accredited with energy capacity, and may require IPL and WPL to adjust their current resource plans, to add resources to meet the requirements of MISO’s process, or procure capacity in the market whereby such costs might not be recovered in rates;
any material post-closing payments related to any past asset divestitures, including the transfer of renewable tax credits, which could result from, among other things, indemnification agreements, warranties, guarantees or litigation;
issues associated with environmental remediation and environmental compliance, including compliance with all current environmental and emissions laws, regulations and permits and future changes in environmental laws and regulations, including the Coal Combustion Residuals Rule, Cross-State Air Pollution Rule and federal, state or local regulations for emissions reductions, including greenhouse gases (GHG), from new and existing fossil-fueled EGUs under the Clean Air Act, and litigation associated with environmental requirements;
increased pressure from customers, investors and other stakeholders to more rapidly reduce GHG emissions;
the timely development of technologies, innovations and advancements to provide cost effective alternatives to traditional energy sources;
the ability to defend against environmental claims brought by state and federal agencies, such as the EPA and state natural resources agencies, or third parties, such as the Sierra Club, and the impact on operating expenses of defending and resolving such claims;
the direct or indirect effects resulting from breakdown or failure of equipment in the operation of electric and gas distribution systems, such as mechanical problems, disruptions in telecommunications, technological problems, and explosions or fires, and compliance with electric and gas transmission and distribution safety regulations, including regulations promulgated by the Pipeline and Hazardous Materials Safety Administration;
issues related to the availability and operations of EGUs and energy storage facilities, including start-up risks, breakdown or failure of equipment, fires, availability of warranty coverage and successful resolution of warranty issues or contract disputes for equipment breakdowns or failures, performance below expected or contracted levels of output or efficiency, operator error, employee safety, transmission constraints, compliance with mandatory reliability standards and risks related to recovery of resulting incremental operating, capacity, fuel-related and capital costs through rates;
impacts that excessive heat, excessive cold, storms, wildfires, or natural disasters may have on Alliant Energy’s, IPL’s and WPL’s operations and construction activities, and recovery of costs associated with restoration activities, or on the operations of Alliant Energy’s investments;
Alliant Energy’s ability to sustain its dividend payout ratio goal;
changes to costs of providing benefits and related funding requirements of pension and OPEB plans due to the market value of the assets that fund the plans, economic conditions, financial market performance, interest rates, timing and form of benefits payments, life expectancies and demographics;
material changes in employee-related benefit and compensation costs, including settlement losses related to pension plans;
risks associated with operation and ownership of non-utility holdings;
changes in technology that alter the channels through which customers buy or utilize Alliant Energy’s, IPL’s or WPL’s products and services;
impacts on equity income from unconsolidated investments from changes in valuations of the assets held, as well as potential changes to ATC’s authorized return on equity;
impacts of IPL’s future tax benefits from Iowa rate-making practices, including deductions for repairs expenditures and cost of removal obligations, allocation of mixed service costs and state depreciation, and recoverability of the associated regulatory assets from customers, when the differences reverse in future periods;
current or future litigation, regulatory investigations, proceedings or inquiries;
reputational damage from negative publicity, protests, fines, penalties and other negative consequences resulting in regulatory and/or legal actions;
the direct or indirect effects resulting from pandemics;
the effect of accounting standards issued periodically by standard-setting bodies;
the ability to successfully complete tax audits and changes in tax accounting methods with no material impact on earnings and cash flows; and
other factors listed in MDA and Risk Factors in Item 1A in the 2024 Form 10-K.
Alliant Energy, IPL and WPL each assume no obligation, and disclaim any duty, to update the forward-looking statements in this report, except as required by law.
Available Information. Alliant Energy routinely posts important information on its website and considers the Investors section of its website, www.alliantenergy.com/investors, a channel of distribution for material information. Information contained on Alliant Energy’s website is not incorporated herein by reference.
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PART I. FINANCIAL INFORMATION
ITEM 1. CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Six Months
Ended June 30,Ended June 30,
2025202420252024
(in millions, except per share amounts)
Revenues:
Electric utility$851$789$1,703$1,580
Gas utility7669316273
Other utility11102524
Non-utility23264448
Total revenues9618942,0881,925
Operating expenses:
Electric production fuel and purchased power150138325301
Electric transmission service151147308300
Cost of gas sold3025167139
Other operation and maintenance:
Asset valuation charge for IPL’s Lansing Generating Station6060
Other168177327336
Depreciation and amortization208188420376
Taxes other than income taxes31296261
Total operating expenses7387641,6091,573
Operating income223130479352
Other (income) and deductions:
Interest expense124108243215
Equity income from unconsolidated investments, net(10)(15)(23)(31)
Allowance for funds used during construction(23)(19)(41)(38)
Other1244
Total other (income) and deductions9276183150
Income before income taxes13154296202
Income tax benefit(43)(33)(91)(43)
Net income attributable to Alliant Energy common shareowners$174$87$387$245
Weighted average number of common shares outstanding:
Basic256.9256.4256.8256.3
Diluted257.3256.7257.3256.6
Earnings per weighted average common share attributable to Alliant Energy common shareowners:
Basic$0.68$0.34$1.51$0.96
Diluted$0.68$0.34$1.50$0.95

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
June 30,
2025
December 31,
2024
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$329$81
Accounts receivable, less allowance for expected credit losses518427
Production fuel, at weighted average cost5254
Gas stored underground, at weighted average cost3155
Materials and supplies, at weighted average cost195186
Regulatory assets164210
Other185171
Total current assets1,4741,184
Property, plant and equipment, net19,37618,701
Investments:
ATC Holdings440415
Other226224
Total investments666639
Other assets:
Regulatory assets2,1232,064
Deferred charges and other111126
Total other assets2,2342,190
Total assets$23,750$22,714
LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt$1,373$1,171
Commercial paper292558
Accounts payable497532
Regulatory liabilities7169
Other346385
Total current liabilities2,5792,715
Long-term debt, net (excluding current portion)9,6428,677
Other liabilities:
Deferred tax liabilities2,1982,188
Regulatory liabilities1,017959
Pension and other benefit obligations202224
Other967947
Total other liabilities4,3844,318
Commitments and contingencies (Note 12)
Equity:
Alliant Energy Corporation common equity:
Common stock - $0.01 par value - 480,000,000 shares authorized; 256,969,227 and 256,690,222 shares outstanding
33
Additional paid-in capital3,0753,060
Retained earnings4,0803,954
Accumulated other comprehensive income1
Shares in deferred compensation trust - 356,799 and 372,116 shares at a weighted average cost of $37.77 and $36.56 per share
(13)(14)
Total Alliant Energy Corporation common equity7,1457,004
Total liabilities and equity$23,750$22,714

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Six Months
Ended June 30,
20252024
(in millions)
Cash flows from operating activities:
Net income$387$245
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization
420376
Deferred tax benefit and tax credits(100)(47)
Asset valuation charge for IPL’s Lansing Generating Station60
Other(1)(4)
Other changes in assets and liabilities:
Accounts receivable(289)(242)
Accounts payable(12)75
Regulatory liabilities71(12)
Deferred income taxes (a)8686
Other(70)25
Net cash flows from operating activities492562
Cash flows used for investing activities:
Construction and acquisition expenditures:
Utility business(976)(870)
Other(89)(90)
Cash receipts on sold receivables198306
Proceeds from sales of partial ownership interests in West Riverside123
Other(27)(2)
Net cash flows used for investing activities(894)(533)
Cash flows from financing activities:
Common stock dividends(261)(246)
Proceeds from issuance of long-term debt1,162969
Payments to retire long-term debt(305)
Net change in commercial paper(266)(423)
Other156
Net cash flows from financing activities6501
Net increase in cash, cash equivalents and restricted cash24830
Cash, cash equivalents and restricted cash at beginning of period8163
Cash, cash equivalents and restricted cash at end of period$329$93
Supplemental cash flows information:
Cash (paid) received during the period for:
Interest($239)($207)
Income taxes, net (a)$91$89
Significant non-cash investing and financing activities:
Accrued capital expenditures$204$272
Beneficial interest obtained in exchange for securitized accounts receivable$235$171
(a)2025 and 2024 include $97 million and $99 million, respectively, of proceeds from renewable tax credits transferred to other corporate taxpayers.

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Six Months
Ended June 30,Ended June 30,
2025202420252024
(in millions)
Revenues:
Electric utility$418$404$848$795
Gas utility4040158148
Steam and other1192423
Total revenues4694531,030966
Operating expenses:
Electric production fuel and purchased power4048107116
Electric transmission service10099207202
Cost of gas sold17178177
Other operation and maintenance:
Asset valuation charge for IPL’s Lansing Generating Station6060
Other84102169187
Depreciation and amortization11597230193
Taxes other than income taxes15142930
Total operating expenses371437823865
Operating income9816207101
Other (income) and deductions:
Interest expense52429984
Allowance for funds used during construction(13)(11)(22)(21)
Other(2)(2)
Total other (income) and deductions37317563
Income (loss) before income taxes61(15)13238
Income tax benefit(37)(33)(77)(43)
Net income$98$18$209$81
Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of IPL’s common stock outstanding during the periods presented.
Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
June 30,
2025
December 31,
2024
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$204$29
Accounts receivable, less allowance for expected credit losses270192
Production fuel, at weighted average cost2430
Gas stored underground, at weighted average cost1125
Materials and supplies, at weighted average cost117113
Regulatory assets8277
Other7243
Total current assets780509
Property, plant and equipment, net9,8219,336
Other assets:
Regulatory assets1,5331,509
Deferred charges and other4653
Total other assets1,5791,562
Total assets$12,180$11,407
LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt$300$300
Commercial paper50
Accounts payable290263
Accounts payable to associated companies4847
Accrued taxes5477
Accrued interest5048
Regulatory liabilities4754
Other7789
Total current liabilities866928
Long-term debt, net (excluding current portion)4,3843,790
Other liabilities:
Deferred tax liabilities1,2301,179
Regulatory liabilities496492
Pension and other benefit obligations4346
Other526511
Total other liabilities2,2952,228
Commitments and contingencies (Note 12)
Equity:
Interstate Power and Light Company common equity:
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding
3333
Additional paid-in capital3,3573,212
Retained earnings1,2451,216
Total Interstate Power and Light Company common equity4,6354,461
Total liabilities and equity$12,180$11,407

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Six Months
Ended June 30,
20252024
(in millions)
Cash flows from operating activities:
Net income$209$81
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization230193
Deferred tax benefit and tax credits(59)(35)
Asset valuation charge for IPL’s Lansing Generating Station60
Other(14)7
Other changes in assets and liabilities:
Accounts receivable(273)(251)
Regulatory assets(47)(1)
Deferred income taxes (a)9892
Other(36)1
Net cash flows from operating activities108147
Cash flows used for investing activities:
Construction and acquisition expenditures(628)(500)
Cash receipts on sold receivables198306
Other(11)(15)
Net cash flows used for investing activities(441)(209)
Cash flows from financing activities:
Common stock dividends(180)(100)
Capital contributions from parent145125
Proceeds from issuance of long-term debt594
Net change in commercial paper(50)
Other(1)(7)
Net cash flows from financing activities50818
Net increase (decrease) in cash, cash equivalents and restricted cash175(44)
Cash, cash equivalents and restricted cash at beginning of period2953
Cash, cash equivalents and restricted cash at end of period$204$9
Supplemental cash flows information:
Cash (paid) received during the period for:
Interest($97)($85)
Income taxes, net (a)$68$92
Significant non-cash investing and financing activities:
Accrued capital expenditures$149$119
Beneficial interest obtained in exchange for securitized accounts receivable$235$171

(a)2025 and 2024 include $73 million and $71 million, respectively, of proceeds from renewable tax credits transferred to other corporate taxpayers.

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Six Months
Ended June 30,Ended June 30,
2025202420252024
(in millions)
Revenues:
Electric utility$433$385$855$785
Gas utility3629158125
Other111
Total revenues4694151,014911
Operating expenses:
Electric production fuel and purchased power11090218186
Electric transmission service514910198
Cost of gas sold1388662
Other operation and maintenance7267137128
Depreciation and amortization9087183178
Taxes other than income taxes15142928
Total operating expenses351315754680
Operating income118100260231
Other (income) and deductions:
Interest expense43418682
Allowance for funds used during construction(10)(8)(19)(17)
Other352
Total other (income) and deductions36337267
Income before income taxes8267188164
Income tax expense (benefit)(5)3(10)8
Net income$87$64$198$156
Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of WPL’s common stock outstanding during the periods presented.
Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
June 30,
2025
December 31,
2024
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$10$51
Accounts receivable, less allowance for expected credit losses234220
Production fuel, at weighted average cost2824
Gas stored underground, at weighted average cost2030
Materials and supplies, at weighted average cost7169
Regulatory assets82133
Prepaid gross receipts tax4951
Other6857
Total current assets562635
Property, plant and equipment, net9,0328,861
Other assets:
Regulatory assets590555
Deferred charges and other5255
Total other assets642610
Total assets$10,236$10,106
LIABILITIES AND EQUITY
Current liabilities:
Commercial paper$292$183
Accounts payable158209
Accrued interest4544
Regulatory liabilities2415
Other8194
Total current liabilities600545
Long-term debt, net3,3713,370
Other liabilities:
Deferred tax liabilities
818865
Regulatory liabilities521467
Pension and other benefit obligations88102
Other658656
Total other liabilities2,0852,090
Commitments and contingencies (Note 12)
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding
6666
Additional paid-in capital2,5332,533
Retained earnings1,5811,502
Total Wisconsin Power and Light Company common equity4,1804,101
Total liabilities and equity$10,236$10,106

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Six Months
Ended June 30,
20252024
(in millions)
Cash flows from operating activities:
Net income$198$156
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization183178
Deferred tax benefit and tax credits(43)(20)
Other(4)(4)
Other changes in assets and liabilities:
Accounts receivable(33)10
Regulatory assets1844
Accounts payable(9)41
Regulatory liabilities655
Other(38)(19)
Net cash flows from operating activities337391
Cash flows used for investing activities:
Construction and acquisition expenditures(348)(370)
Proceeds from sales of partial ownership interests in West Riverside123
Other(14)
Net cash flows used for investing activities(362)(247)
Cash flows used for financing activities:
Common stock dividends(119)(98)
Capital contributions from parent55
Proceeds from issuance of long-term debt297
Net change in commercial paper109(318)
Other(6)(7)
Net cash flows used for financing activities(16)(71)
Net increase (decrease) in cash, cash equivalents and restricted cash(41)73
Cash, cash equivalents and restricted cash at beginning of period517
Cash, cash equivalents and restricted cash at end of period$10$80
Supplemental cash flows information:
Cash (paid) received during the period for:
Interest($88)($76)
Income taxes, net (a)$8($10)
Significant non-cash investing and financing activities:
Accrued capital expenditures$48$146

(a)2025 and 2024 include $24 million and $28 million, respectively, of proceeds from renewable tax credits transferred to other corporate taxpayers.

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
INTERSTATE POWER AND LIGHT COMPANY
WISCONSIN POWER AND LIGHT COMPANY

COMBINED NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)

NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (SEC). Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the 2024 Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the six months ended June 30, 2025 are not necessarily indicative of results that may be expected for the year ending December 31, 2025.

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

NOTE 1(b) Cash and Cash Equivalents - At June 30, 2025, cash and cash equivalents included money market fund investments and time deposits of $303 million and $194 million for Alliant Energy and IPL, respectively, with weighted average interest rates of 4%.

NOTE 1(c) Asset Retirement Obligations (AROs) - In the second quarter of 2024, substantially due to the enactment of the revised Coal Combustion Residuals Rule, Alliant Energy and IPL recorded a pre-tax non-cash charge of $20 million to “Other operation and maintenance” in their income statements for the AROs allocated to IPL’s steam business for its Prairie Creek Generating Station and the retired Sixth Street Generating Station as established in prior rate reviews.

NOTE 2. REGULATORY MATTERS
Regulatory Assets and Regulatory Liabilities -
Regulatory assets were comprised of the following items (in millions):
Alliant EnergyIPLWPL
June 30,
2025
December 31,
2024
June 30,
2025
December 31,
2024
June 30,
2025
December 31,
2024
Tax-related$1,030$989$897$870$133$119
AROs427401296281131120
Pension and OPEB costs306315153157153158
Assets retired early1671801571681012
Derivatives576014154345
Non-service pension and OPEB costs545120193432
Commodity cost recovery49681023966
WPL’s Western Wisconsin gas distribution expansion investments40424042
Other15716868748994
$2,287$2,274$1,615$1,586$672$688

Assets retired early - IPL’s retail electric rate review for the October 2024 through September 2025 forward-looking Test Period filed with the IUC in October 2023 included a request for continued recovery of and a return on the remaining net book value of IPL’s Lansing Generating Station through 2037. In June 2024, IPL reached a partial non-unanimous settlement agreement with certain stakeholders, which the IUC subsequently approved in September 2024. The agreement included a return of the remaining net book value of Lansing, but did not include a return on the remaining net book value of Lansing. As a result, the return on the remaining net book value is no longer probable of recovery from IPL’s retail electric customers and in the second quarter of 2024, a pre-tax non-cash charge of $60 million was recorded to “Asset valuation charge for IPL’s Lansing Generating Station” in Alliant Energy’s and IPL’s income statements.

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Regulatory liabilities were comprised of the following items (in millions):
Alliant EnergyIPLWPL
June 30,
2025
December 31,
2024
June 30,
2025
December 31,
2024
June 30,
2025
December 31,
2024
Tax-related$611$582$275$286$336$296
Cost of removal obligations349347206205143142
Derivatives605332292824
Other684630263820
$1,088$1,028$543$546$545$482

Tax-related - The increase in Alliant Energy’s and WPL’s tax-related regulatory liabilities was primarily due to tax benefits resulting from WPL electing investment tax credit treatment for certain energy storage facilities in 2025.

NOTE 3. RECEIVABLES
Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. Effective May 2025, the limit on cash proceeds under the Receivables Agreement was changed to $5 million. As of June 30, 2025, IPL had $4 million of available capacity under its sales of accounts receivable program. IPL’s maximum and average outstanding aggregate cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and six months ended June 30 were as follows (in millions):
Three MonthsSix Months
2025202420252024
Maximum outstanding aggregate cash proceeds$110$110$110$110
Average outstanding aggregate cash proceeds60738448

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):
June 30, 2025December 31, 2024
Customer accounts receivable$135$137
Unbilled utility revenues114108
Receivables sold to third party249245
Less: cash proceeds170
Deferred proceeds248175
Less: allowance for expected credit losses1312
Fair value of deferred proceeds$235$163

As of June 30, 2025, outstanding receivables past due under the Receivables Agreement were $16 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and six months ended June 30 were as follows (in millions):
Three MonthsSix Months
2025202420252024
Collections$445$456$1,052$1,013
Write-offs, net of recoveries2245

NOTE 4. INVESTMENTS
Unconsolidated Equity Investments - Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three and six months ended June 30 was as follows (in millions):
Three MonthsSix Months
2025202420252024
ATC Holdings($14)($13)($28)($25)
Non-utility wind farm in Oklahoma(3)(2)(4)(3)
Corporate venture investments711(1)
Other(2)(2)
($10)($15)($23)($31)

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NOTE 5. COMMON EQUITY
Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2025
256,690,222 
Shareowner Direct Plan192,628 
Equity-based compensation plans86,377 
Shares outstanding, June 30, 2025
256,969,227 

At-the-Market Offering Program - In May 2025, Alliant Energy filed a prospectus supplement and executed a related distribution agreement, under which it may sell up to $1.3 billion in aggregate of its common stock through 2028 through an at-the-market offering program that includes an equity forward sales component. Alliant Energy expects to use proceeds from the issuance of common stock for general corporate purposes.

In the second quarter of 2025, Alliant Energy entered into forward sale agreements under its at-the-market offering program with various counterparties who borrowed and sold an aggregate of 2,913,023 shares of Alliant Energy common stock at an aggregate gross sales price of $179 million, including approximately $2 million in commissions, to the counterparties payable by Alliant Energy when the forward sale agreements are settled. Alliant Energy has not yet received any proceeds from this program and no amounts have been or will be recorded in equity on Alliant Energy’s balance sheets until the forward sale agreements settle. Alliant Energy expects to settle the forward sale agreements prior to December 31, 2026 through physical delivery of shares of common stock in exchange for cash proceeds at the then-applicable forward sale price; however, Alliant Energy may elect cash settlement or net share settlement for all or a portion of the obligations under the forward sale agreements. As of June 30, 2025, the weighted-average forward price, net of commissions, was $60.84 per share and is subject to daily adjustment based on a floating interest rate factor and decreased by other fixed amounts specified in the forward sale agreements. As of June 30, 2025, Alliant Energy could have settled all of its outstanding forward sale agreements under the at-the-market offering program with physical delivery of 2,913,023 shares of Alliant Energy common stock to the counterparties in exchange for cash of $177 million.

Alliant Energy has concluded that the forward sale agreements meet the derivative scope exception for certain contracts involving an entity’s own equity. Until settlement of the forward sale agreements, Alliant Energy’s EPS dilution resulting from the agreements, if any, is determined using the treasury stock method. Share dilution occurs when the average market price of Alliant Energy stock during the reporting period is higher than the forward sale price as of the end of the reporting period. As of June 30, 2025, 26,986 incremental shares were included in the calculation of diluted EPS related to the securities under the forward sale agreements.

Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):
Alliant EnergyAccumulatedShares in
AdditionalOtherDeferredTotal
CommonPaid-InRetainedComprehensiveCompensationCommon
StockCapitalEarningsIncomeTrustEquity
Three Months Ended June 30, 2025
Beginning balance, March 31, 2025
$3$3,066$4,037$($13)$7,093
Net income attributable to Alliant Energy common shareowners174174
Common stock dividends ($0.5075 per share)
(131)(131)
Shareowner Direct Plan issuances66
Equity-based compensation plans and other33
Ending balance, June 30, 2025
$3$3,075$4,080$($13)$7,145
Three Months Ended June 30, 2024
Beginning balance, March 31, 2024
$3$3,033$3,791$2($12)$6,817
Net income attributable to Alliant Energy common shareowners8787
Common stock dividends ($0.48 per share)
(123)(123)
Shareowner Direct Plan issuances66
Equity-based compensation plans and other33
Other comprehensive income, net of tax11
Ending balance, June 30, 2024
$3$3,042$3,755$3($12)$6,791
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Alliant EnergyAccumulatedShares in
AdditionalOtherDeferredTotal
CommonPaid-InRetainedComprehensiveCompensationCommon
StockCapitalEarningsIncome (Loss)TrustEquity
Six Months Ended June 30, 2025
Beginning balance, December 31, 2024
$3$3,060$3,954$1($14)$7,004
Net income attributable to Alliant Energy common shareowners387387
Common stock dividends ($1.015 per share)
(261)(261)
Shareowner Direct Plan issuances1212
Equity-based compensation plans and other314
Other comprehensive loss, net of tax(1)(1)
Ending balance, June 30, 2025
$3$3,075$4,080$($13)$7,145
Six Months Ended June 30, 2024
Beginning balance, December 31, 2023
$3$3,030$3,756$1($13)$6,777
Net income attributable to Alliant Energy common shareowners245245
Common stock dividends ($0.96 per share)
(246)(246)
Shareowner Direct Plan issuances1212
Equity-based compensation plans and other11
Other comprehensive income, net of tax22
Ending balance, June 30, 2024
$3$3,042$3,755$3($12)$6,791
IPLAdditionalTotal
CommonPaid-InRetainedCommon
StockCapitalEarningsEquity
Three Months Ended June 30, 2025
Beginning balance, March 31, 2025
$33$3,257$1,237$4,527
Net income9898
Common stock dividends(90)(90)
Capital contributions from parent100100
Ending balance, June 30, 2025
$33$3,357$1,245$4,635
Three Months Ended June 30, 2024
Beginning balance, March 31, 2024
$33$2,937$1,067$4,037
Net income1818
Common stock dividends(50)(50)
Capital contributions from parent7575
Ending balance, June 30, 2024
$33$3,012$1,035$4,080
IPLAdditionalTotal
CommonPaid-InRetainedCommon
StockCapitalEarningsEquity
Six Months Ended June 30, 2025
Beginning balance, December 31, 2024
$33$3,212$1,216$4,461
Net income209209
Common stock dividends(180)(180)
Capital contributions from parent145145
Ending balance, June 30, 2025
$33$3,357$1,245$4,635
Six Months Ended June 30, 2024
Beginning balance, December 31, 2023
$33$2,887$1,054$3,974
Net income8181
Common stock dividends(100)(100)
Capital contributions from parent125125
Ending balance, June 30, 2024
$33$3,012$1,035$4,080
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WPLAdditionalTotal
CommonPaid-InRetainedCommon
StockCapitalEarningsEquity
Three Months Ended June 30, 2025
Beginning balance, March 31, 2025
$66$2,533$1,537$4,136
Net income8787
Common stock dividends(43)(43)
Ending balance, June 30, 2025
$66$2,533$1,581$4,180
Three Months Ended June 30, 2024
Beginning balance, March 31, 2024
$66$2,533$1,396$3,995
Net income6464
Common stock dividends(49)(49)
Ending balance, June 30, 2024
$66$2,533$1,411$4,010
WPLAdditionalTotal
CommonPaid-InRetainedCommon
StockCapitalEarningsEquity
Six Months Ended June 30, 2025
Beginning balance, December 31, 2024
$66$2,533$1,502$4,101
Net income198198
Common stock dividends(119)(119)
Ending balance, June 30, 2025
$66$2,533$1,581$4,180
Six Months Ended June 30, 2024
Beginning balance, December 31, 2023
$66$2,478$1,353$3,897
Net income156156
Common stock dividends(98)(98)
Capital contributions from parent5555
Ending balance, June 30, 2024
$66$2,533$1,411$4,010

NOTE 6. DEBT
NOTE 6(a) Short-term Debt - In March 2025, Alliant Energy, IPL and WPL reallocated credit facility capacity amounts to $550 million for Alliant Energy at the parent company level, $350 million for IPL and $400 million for WPL, within the $1.3 billion total commitment. Information regarding commercial paper and borrowings under the single credit facility classified as short-term debt was as follows (dollars in millions):
June 30, 2025Alliant EnergyIPLWPL
Amount outstanding$292$$292
Weighted average interest rates4.6%N/A4.6%
Available credit facility capacity$1,008$350$108
Alliant EnergyIPLWPL
Three Months Ended June 30202520242025202420252024
Maximum amount outstanding (based on daily outstanding balances)$741$435$141$19$292$57
Average amount outstanding (based on daily outstanding balances)$449$275$33$2$225$8
Weighted average interest rates4.6%5.5%4.6%5.5%4.6%5.4%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)$741$632$141$19$292$390
Average amount outstanding (based on daily outstanding balances)$495$381$43$1$193$131
Weighted average interest rates4.6%5.5%4.6%5.5%4.6%5.5%

NOTE 6(b) Long-term Debt - In March 2025, AEF entered into a $300 million variable rate (5% as of June 30, 2025) term loan credit agreement (with Alliant Energy as guarantor), which expires in March 2026. This term loan credit agreement amended and restated the term loan credit agreement that expired in March 2025, and retired the $300 million variable rate term loan set forth therein. AEF’s restated term loan credit agreement includes an option to increase the amount outstanding with one or more additional term loans in an aggregate amount not to exceed $100 million.

In May 2025, IPL issued $600 million of 5.6% senior debentures due 2035. A portion of the net proceeds from this issuance was used for the July 2025 retirement of IPL’s $50 million 5.5% senior debentures and placed in money market fund investments and time deposits pending the August 2025 retirement of IPL’s $250 million 3.4% senior debentures, a portion was used to reduce cash amounts received from its sale of accounts receivable program and commercial paper classified as long-term debt, and the remainder of the net proceeds was used for general corporate purposes.
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Convertible Senior Notes - In May 2025, Alliant Energy issued $575 million of 3.25% convertible senior notes (the 2028 Notes), which are senior unsecured obligations, and used the net proceeds from the issuance to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. The 2028 Notes will mature on May 30, 2028 unless earlier converted or repurchased, and no sinking fund is provided for the 2028 Notes. Alliant Energy may not redeem the 2028 Notes prior to the maturity date. Holders may convert their 2028 Notes at their option at any time prior to the close of business on the business day immediately preceding March 1, 2028 only under the following circumstances:

during any calendar quarter commencing after the calendar quarter ending on September 30, 2025 (and only during such calendar quarter), if the last reported sale price of Alliant Energy’s common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day during such period;
during the 5 business day period after any 10 consecutive trading day period (the “measurement period”) in which the trading price (as defined in the related Indenture) per $1,000 principal amount of 2028 Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of Alliant Energy’s common stock and the conversion rate on each such trading day; or
upon the occurrence of specified corporate events.

On or after March 1, 2028 until the close of business on the business day immediately preceding the maturity date, holders may convert all or any portion of their 2028 Notes at any time, regardless of the foregoing circumstances. Upon conversion of the 2028 Notes, Alliant Energy will pay cash up to the aggregate principal amount of the 2028 Notes to be converted and pay or deliver, as the case may be, cash, shares of its common stock or a combination of cash and shares of its common stock, at its election, in respect of the remainder, if any, of its conversion obligation in excess of the aggregate principal amount of the 2028 Notes being converted.

The initial conversion rate is 13.1773 shares of common stock per $1,000 principal amount of 2028 Notes (equivalent to an initial conversion price of approximately $75.89 per share of Alliant Energy’s common stock). The conversion rate is subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest. In addition, following certain corporate events that occur prior to the maturity date, Alliant Energy will, in certain circumstances, increase the conversion rate for a holder who elects to convert its 2028 Notes in connection with such a corporate event.

If Alliant Energy undergoes a fundamental change (as defined in the related Indenture), then, subject to certain conditions, holders of the 2028 Notes may require Alliant Energy to repurchase for cash all or any portion of its 2028 Notes at a fundamental change repurchase price equal to 100% of the principal amount of the 2028 Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date.

As of June 30, 2025, the conditions allowing holders of the 2028 Notes and Alliant Energy’s convertible senior notes due 2026 (the 2026 Notes) to convert their respective notes were not met, and the 2028 Notes were classified as “Long-term debt, net” and the 2026 Notes were classified as “Current maturities of long-term debt,” on Alliant Energy’s balance sheet. As of June 30, 2025, the net carrying amount was $568 million and $573 million, with unamortized debt issuance costs of $7 million and $2 million, and the estimated fair value (Level 2) was $574 million and $592 million for the 2028 Notes and 2026 Notes, respectively. As of June 30, 2025, there were no shares of Alliant Energy’s common stock related to the potential conversion of the 2028 Notes and 2026 Notes included in diluted EPS based on Alliant Energy’s average stock prices and the relevant terms of the respective notes.

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NOTE 7. REVENUES
Disaggregation of revenues from contracts with customers is provided for each reportable segment (IPL and WPL), as well as by customer class within electric and gas sales, as follows (in millions):
Alliant EnergyIPLWPL
Three Months Ended June 30202520242025202420252024
Electric Utility:
Retail - residential$295$291$142$151$153$140
Retail - commercial2111911351187673
Retail - industrial240237118118122119
Wholesale494314133530
Bulk power and other5627944723
Total Electric Utility851789418404433385
Gas Utility:
Retail - residential413821222016
Retail - commercial20191011108
Retail - industrial322111
Transportation/other12107654
Total Gas Utility766940403629
Other Utility:
Steam9999
Other utility2121
Total Other Utility11101191
Non-Utility and Other:
Travero and other2326
Total Non-Utility and Other2326
Total revenues$961$894$469$453$469$415
Alliant EnergyIPLWPL
Six Months Ended June 30202520242025202420252024
Electric Utility:
Retail - residential$618$588$297$301$321$287
Retail - commercial425377271232154145
Retail - industrial475460236229239231
Wholesale978928266963
Bulk power and other88661677259
Total Electric Utility1,7031,580848795855785
Gas Utility:
Retail - residential18816595909375
Retail - commercial948043415139
Retail - industrial864442
Transportation/other26221613109
Total Gas Utility316273158148158125
Other Utility:
Steam19201920
Other utility645311
Total Other Utility2524242311
Non-Utility and Other:
Travero and other4448
Total Non-Utility and Other4448
Total revenues$2,088$1,925$1,030$966$1,014$911

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NOTE 8. INCOME TAXES
Income Tax Rates - Overall effective income tax rates for the three and six months ended June 30, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, investment tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. Also impacting Alliant Energy’s and IPL’s effective income tax rates for the three and six months ended June 30, 2024 were the pre-tax non-cash charge of $60 million for IPL’s Lansing Generating Station discussed in Note 2 and the pre-tax non-cash charge of $20 million for the AROs allocated to IPL’s steam business discussed in Note 1(c). Alliant Energy’s, IPL’s and WPL’s effective income tax rates for the three and six months ended June 30, 2025 were also impacted by additional tax credits in 2025 from renewable generation and energy storage projects placed in service in 2024 and/or expected to be placed in service in 2025.
Alliant EnergyIPLWPL
Three MonthsSix Months Three MonthsSix Months Three MonthsSix Months
202520242025202420252024202520242025202420252024
Overall income tax rate(33%)(61%)(31%)(21%)(61%)220%(58%)(113%)(6%)4%(5%)5%

Deferred Tax Assets and Liabilities -
Carryforwards - At June 30, 2025, the carryforwards and expiration dates were estimated as follows (in millions):
Range of Expiration DatesAlliant EnergyIPLWPL
State net operating losses2025-2045$323$7$1
Federal tax credits2033-2045678437228

NOTE 9. BENEFIT PLANS
NOTE 9(a) Pension and OPEB Plans -
Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included below (in millions). For IPL and WPL, amounts are for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.
Defined Benefit Pension PlansOPEB Plans
Three MonthsSix MonthsThree MonthsSix Months
Alliant Energy20252024202520242025202420252024
Service cost$1$1$2$2$1$1$1$1
Interest cost121123222244
Expected return on plan assets(14)(14)(27)(27)(2)(1)(3)(2)
Amortization of actuarial loss561112
$4$4$9$9$1$2$2$3
Defined Benefit Pension PlansOPEB Plans
Three MonthsSix MonthsThree MonthsSix Months
IPL20252024202520242025202420252024
Service cost$$$1$1$$$$
Interest cost5510101122
Expected return on plan assets(6)(6)(12)(13)(1)(1)(2)(2)
Amortization of actuarial loss2345
$1$2$3$3$$$$
Defined Benefit Pension PlansOPEB Plans
Three MonthsSix MonthsThree MonthsSix Months
WPL20252024202520242025202420252024
Service cost$1$1$1$1$$$$
Interest cost551010112
Expected return on plan assets(6)(6)(12)(12)
Amortization of actuarial loss2356
$2$3$4$5$$1$1$2

NOTE 9(b) Equity-based Compensation Plans - A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):
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Alliant EnergyIPLWPL
Three MonthsSix Months Three MonthsSix Months Three MonthsSix Months
202520242025202420252024202520242025202420252024
Compensation expense$3$3$7$7$2$2$4$4$1$1$3$3
Income tax benefits11221111

As of June 30, 2025, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $21 million, $10 million and $10 million, respectively, which is expected to be recognized over a weighted average period of between 1 year and 2 years.

For the six months ended June 30, 2025, performance shares and restricted stock units were granted to key employees under the equity-based compensation plans as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards.
Weighted Average
GrantsGrant Date Fair Value
Performance shares (total shareowner return metric)105,523$66.51
Performance shares (net income and environmental metrics)118,45761.61
Restricted stock units98,82161.62

As of June 30, 2025, 397,023 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

NOTE 10. DERIVATIVE INSTRUMENTS
Commodity Derivatives -
Notional Amounts - As of June 30, 2025, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):
ElectricityFTRsNatural GasDiesel Fuel
MWhsYearsMWhsYearsDthsYearsGallonsYears
Alliant Energy
1,911 2025-202624,310 2025-2026153,204 2025-20321,260 2025
IPL523 2025-20269,555 2025-202666,568 2025-2030 
WPL1,388 2025-202614,755 2025-202686,636 2025-20321,260 2025

Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):
Alliant EnergyIPLWPL
June 30,
2025
December 31,
2024
June 30,
2025
December 31,
2024
June 30,
2025
December 31,
2024
Current derivative assets$75$41$53$29$22$12
Non-current derivative assets303416191415
Current derivative liabilities23269111415
Non-current derivative liabilities3032322730

During the six months ended June 30, 2025, Alliant Energy’s, IPL’s and WPL’s derivative assets increased primarily due to new FTRs resulting from the annual FTR auction in the second quarter of 2025 operated by MISO. Based on IPL’s and WPL’s cost recovery mechanisms, the changes in the fair value of derivative liabilities/assets result in comparable changes to regulatory assets/liabilities on the balance sheets.

Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At June 30, 2025 and December 31, 2024, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered.

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Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, derivative assets and derivative liabilities related to commodity contracts would have been presented on the balance sheets as follows (in millions):
Alliant EnergyIPLWPL
GrossGrossGross
(as reported)Net(as reported)Net(as reported)Net
June 30, 2025
Derivative assets$105$90$69$61$36$29
Derivative liabilities53381244134
December 31, 2024
Derivative assets756448432721
Derivative liabilities58471384539

Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement.

NOTE 11. FAIR VALUE MEASUREMENTS
Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):
Alliant EnergyJune 30, 2025December 31, 2024
Fair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123Total
Assets:
Money market fund investments and time deposits$303 $303 $ $ $303 $52 $52 $ $ $52 
Commodity derivatives105  48 57 105 75  48 27 75 
Deferred proceeds235   235 235 163   163 163 
Liabilities:
Commodity derivatives53  52 1 53 58  56 2 58 
Long-term debt (incl. current maturities)11,015  10,617  10,617 9,848  9,577  9,577 
IPLJune 30, 2025December 31, 2024
Fair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123Total
Assets:
Money market fund investments and time deposits$194 $194 $ $ $194 $9 $9 $ $ $9 
Commodity derivatives69  24 45 69 48  26 22 48 
Deferred proceeds235   235 235 163   163 163 
Liabilities:
Commodity derivatives12  11 1 12 13  11 2 13 
Long-term debt (incl. current maturities)4,684  4,408  4,408 4,090  3,736  3,736 
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WPLJune 30, 2025December 31, 2024
Fair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123Total
Assets:
Money market fund investments$ $ $ $ $ $43 $43 $ $ $43 
Commodity derivatives36  24 12 36 27  22 5 27 
Liabilities:
Commodity derivatives41  41  41 45  45  45 
Long-term debt3,371  3,238  3,238 3,370  3,170  3,170 

Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions):
Alliant EnergyCommodity Contract Derivative
Assets and (Liabilities), netDeferred Proceeds
Three Months Ended June 302025202420252024
Beginning balance, April 1 $9$7$86$184
Total net gains (losses) included in changes in net assets (realized/unrealized)
10(5)
Purchases5059
Sales(1)(1)
Settlements (a)(12)(9)149(13)
Ending balance, June 30
$56$51$235$171
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30
$10($5)$$
Alliant EnergyCommodity Contract Derivative
Assets and (Liabilities), netDeferred Proceeds
Six Months Ended June 302025202420252024
Beginning balance, January 1$25$24$163$216
Total net gains (losses) included in changes in net assets (realized/unrealized)
8(8)
Purchases5059
Sales(1)(1)
Settlements (a)(26)(23)72(45)
Ending balance, June 30
$56$51$235$171
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30
$8($8)$$
IPLCommodity Contract Derivative
Assets and (Liabilities), netDeferred Proceeds
Three Months Ended June 302025202420252024
Beginning balance, April 1 $9$5$86$184
Total net gains (losses) included in changes in net assets (realized/unrealized)
6(2)
Purchases4045
Sales(1)(1)
Settlements (a)(10)(7)149(13)
Ending balance, June 30
$44$40$235$171
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30
$6($2)$$
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IPLCommodity Contract Derivative
Assets and (Liabilities), netDeferred Proceeds
Six Months Ended June 302025202420252024
Beginning balance, January 1$20$19$163$216
Total net gains (losses) included in changes in net assets (realized/unrealized)
6(6)
Purchases4045
Sales(1)(1)
Settlements (a)(21)(17)72(45)
Ending balance, June 30
$44$40$235$171
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30
$6($6)$$
WPLCommodity Contract Derivative
Assets and (Liabilities), net
Three Months Ended June 3020252024
Beginning balance, April 1 $$2
Total net gains (losses) included in changes in net assets (realized/unrealized)
4(3)
Purchases1014
Settlements(2)(2)
Ending balance, June 30
$12$11
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30
$4($3)
WPLCommodity Contract Derivative
Assets and (Liabilities), net
Six Months Ended June 3020252024
Beginning balance, January 1$5$5
Total net gains (losses) included in changes in net assets (realized/unrealized)
2(2)
Purchases1014
Settlements(5)(6)
Ending balance, June 30
$12$11
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30
$2($2)

(a)Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for expected credit losses associated with the receivables sold and cash amounts received from the receivables sold.

Commodity Contracts - The fair value of FTRs and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):
Alliant EnergyIPLWPL
Excluding FTRsFTRsExcluding FTRsFTRsExcluding FTRsFTRs
June 30, 2025$6$50$6$38$$12
December 31, 202425205

NOTE 12. COMMITMENTS AND CONTINGENCIES
NOTE 12(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects, including improvements at the natural gas-fired Neenah Energy Facility and Sheboygan Falls Energy Facility, and IPL’s and WPL’s expansion of energy storage. At June 30, 2025, Alliant Energy’s, IPL’s and WPL’s minimum future commitments for these projects were $287 million, $128 million and $157 million, respectively.

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NOTE 12(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At June 30, 2025, the related minimum future commitments, excluding amounts for purchased power commitments that do not have minimum thresholds but will require payment when electricity is generated by the provider, were as follows (in millions):
Alliant EnergyIPLWPL
Natural gas$783$439$344
Coal1386177
Other (a)1175329
$1,038$553$450

(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2025.

NOTE 12(c) Guarantees and Indemnifications -
Whiting Petroleum Corporation (Whiting Petroleum) - In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum, an independent oil and gas company. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, has guaranteed the partnership obligations of an affiliate of Whiting Petroleum under multiple general partnership agreements in the oil and gas industry. The guarantees do not include a maximum limit. Based on information made available to Alliant Energy by Whiting Petroleum, the Whiting Petroleum affiliate holds an approximate 6% share in the partnerships, and currently known obligations include costs associated with the future abandonment of certain facilities owned by the partnerships. The general partnerships were formed under California law, and Alliant Energy Resources, LLC may need to perform under the guarantees if the affiliate of Whiting Petroleum is unable to meet its partnership obligations.

Whiting Petroleum previously completed bankruptcy proceedings and business combinations, which substantially reduce the likelihood that Alliant Energy will be obligated to make any payments under these guarantees. As of June 30, 2025, the currently known partnership obligations for the abandonment obligations are estimated at $54 million, which represents Alliant Energy’s currently estimated maximum exposure under the guarantees. Alliant Energy is not currently aware of, nor does it currently expect to incur in the future, any material liabilities related to these guarantees and therefore has not recognized any material liabilities related to these guarantees as of June 30, 2025 and December 31, 2024.

Non-utility Wind Farm in Oklahoma - In 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third party under a long-term purchased power agreement (PPA). Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $43 million as of June 30, 2025 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of June 30, 2025 and December 31, 2024.

Transfers of Renewable Tax Credits - IPL and WPL have entered into agreements to transfer renewable tax credits from certain wind, solar and energy storage facilities to other corporate taxpayers in exchange for cash. As of June 30, 2025, IPL and WPL provided indemnifications associated with $266 million and $145 million, respectively, of proceeds for renewable tax credits transferred to other corporate taxpayers in the event of an adverse interpretation of tax law, including whether the related tax credits meet the qualification requirements. Alliant Energy, IPL and WPL believe the likelihood of having to make any material cash payments under these indemnifications is remote.

Electric Transmission Infrastructure - IPL and WPL have entered into agreements with their respective electric transmission service providers related to the construction of infrastructure necessary for the data centers that are expected to be built in IPL’s and WPL’s service territories by certain of their customers. If these construction projects were to be terminated prior to the infrastructure being placed in service by the electric transmission service providers, then IPL or WPL must reimburse their respective provider for the related costs incurred to-date. As of June 30, 2025, IPL’s and WPL’s related guarantees were approximately $24 million and $40 million, respectively. Alliant Energy, IPL and WPL are not aware of any material liabilities related to these guarantees that it is probable that they will be obligated to pay and therefore have not recognized any material liabilities related to these guarantees as of June 30, 2025.

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NOTE 12(d) Environmental Matters -
Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At June 30, 2025, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions):
Alliant EnergyIPLWPL
Range of estimated future costs$8 
-
$30$6 
-
$19$2 
-
$11
Current and non-current environmental liabilities$13$8$5

IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential Clean Air Act issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers.

Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however, future capital investments and/or modifications to EGUs and electric and gas distribution systems to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Cross-State Air Pollution Rule, Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of GHG, including the Clean Air Act.

NOTE 13. SEGMENTS OF BUSINESS
Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s reportable segments, which represents the services provided to their customers, and reconciliation to consolidated amounts, was as follows (in millions):
Utility
TotalAlliant
ReportableEnergy
Three Months Ended June 30, 2025IPLWPLSegmentsOtherConsolidated
Electric utility revenues$418$433$851N/A$851
Gas utility revenues403676N/A76
Other revenues1111$2334
Total revenues46946993823961
Electric production fuel and purchased power expense40110150N/A150
Electric transmission service expense10051151N/A151
Cost of gas sold expense171330N/A30
Other operation and maintenance expense847215612168
Other segment items:
Depreciation and amortization expense115902053208
Interest expense52439529124
Equity income from unconsolidated investments, net(1)(1)(9)(10)
Income tax benefit(37)(5)(42)(1)(43)
Other (a)999
Net income (loss)9887185(11)174
Total assets (as of June 30, 2025)
12,18010,23622,4161,33423,750
Investments in equity method subsidiaries (as of June 30, 2025)
51823622645
Construction and acquisition expenditures25217042261483
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Utility
TotalAlliant
Three Months Ended June 30, 2024 (amounts may not foot due to rounding)
ReportableEnergy
IPLWPLSegmentsOtherConsolidated
Electric utility revenues$404$385$789N/A$789
Gas utility revenues402969N/A69
Other revenues9110$2636
Total revenues45341586826894
Electric production fuel and purchased power expense4890138N/A138
Electric transmission service expense9949148N/A147
Cost of gas sold expense17825N/A25
Asset valuation charge for IPL’s Lansing Generating Station6060N/A60
Other operation and maintenance expense102671698177
Other segment items:
Depreciation and amortization expense97871844188
Interest expense42418325108
Equity income from unconsolidated investments, net(1)(1)(14)(15)
Income tax expense (benefit)(33)3(30)(3)(33)
Other (a)3710112
Net income186482587
Total assets (as of June 30, 2024)
10,7329,92520,6571,17921,836
Investments in equity method subsidiaries (as of June 30, 2024)
51722584606
Construction and acquisition expenditures24714539258450
Utility
TotalAlliant
ReportableEnergy
Six Months Ended June 30, 2025IPLWPLSegmentsOtherConsolidated
Electric utility revenues$848$855$1,703N/A$1,703
Gas utility revenues158158316N/A316
Other revenues24125$4469
Total revenues1,0301,0142,044442,088
Electric production fuel and purchased power expense107218325N/A325
Electric transmission service expense207101308N/A308
Cost of gas sold expense8186167N/A167
Other operation and maintenance expense16913730621327
Other segment items:
Depreciation and amortization expense2301834137420
Interest expense998618558243
Equity income from unconsolidated investments, net(1)(1)(22)(23)
Income tax benefit(77)(10)(87)(4)(91)
Other (a)51621425
Net income (loss)209198407(20)387
Construction and acquisition expenditures628348976891,065

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Utility
TotalAlliant
Six Months Ended June 30, 2024 (amounts may not foot due to rounding)
ReportableEnergy
IPLWPLSegmentsOtherConsolidated
Electric utility revenues$795$785$1,580N/A$1,580
Gas utility revenues148125273N/A273
Other revenues23124$4872
Total revenues9669111,877481,925
Electric production fuel and purchased power expense116186302N/A301
Electric transmission service expense20298300N/A300
Cost of gas sold expense7762139N/A139
Asset valuation charge for IPL’s Lansing Generating Station6060N/A60
Other operation and maintenance expense18712831521336
Other segment items:
Depreciation and amortization expense1931783715376
Interest expense848216649215
Equity income from unconsolidated investments, net(1)(1)(30)(31)
Income tax expense (benefit)(43)8(35)(8)(43)
Other (a)91423327
Net income811562378245
Construction and acquisition expenditures50037087090960

(a)Other segment items for each reportable segment include allowance for funds used during construction, taxes other than income taxes, interest income, and other miscellaneous income and deductions.

NOTE 14. RELATED PARTIES
Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three and six months ended June 30 were as follows (in millions):
IPLWPL
Three MonthsSix Months Three MonthsSix Months
20252024202520242025202420252024
Corporate Services billings$50$49$97$92$48$46$95$86
Sales credited1240146236
Purchases billed10710520020116163523

Net intercompany payables to Corporate Services were as follows (in millions):
IPLWPL
June 30, 2025December 31, 2024June 30, 2025December 31, 2024
Net payables to Corporate Services$135$135$50$64

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three and six months ended June 30 were as follows (in millions):
Three MonthsSix Months
2025202420252024
ATC billings to WPL$38$39$76$76
WPL billings to ATC54117

WPL owed ATC net amounts of $10 million as of June 30, 2025 and $10 million as of December 31, 2024.

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

This MDA includes information relating to Alliant Energy, and IPL and WPL (collectively, the Utilities), as well as ATC Holdings, AEF and Corporate Services. Where appropriate, information relating to a specific entity has been segregated and labeled as such. The following discussion and analysis should be read in conjunction with the Financial Statements and the Notes included in this report, as well as the financial statements, notes and MDA included in the 2024 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.

2025 HIGHLIGHTS

Key highlights since the filing of the 2024 Form 10-K include the following:

Customer Investments:
Over the next six years, Alliant Energy currently plans to develop and/or acquire new generation investments to add flexibility with evolving load growth, including approximately 1,500 MW of new natural gas resources, approximately 1,200 MW of new wind generation, approximately 800 MW of new energy storage, refurbishments at approximately 500 MW of existing wind farms, improvements of approximately 280 MW at existing natural gas-fired EGUs, and the conversion of existing coal-fired EGUs to natural gas. Alliant Energy is currently evaluating the impact of potential additional large load growth customers and MISO’s seasonal resource adequacy requirements on its resource plans and will update these generation investment plans as needed in the future. Estimated capital expenditures for these planned projects for 2025 through 2028 are included in the “Generation” section in the construction and acquisition table in “Liquidity and Capital Resources.” Information on IPL’s and WPL’s regulatory filings and/or approvals for future generation and energy storage projects are as follows:
In February 2025, WPL filed a certificate of authority (CA) application with the PSCW for approval to construct a 2 billion cubic feet, or 25 million gallon, liquified natural gas facility in Rock County, Wisconsin. A decision from the PSCW is currently expected in the second quarter of 2026.
In April 2025, the PSCW issued an order authorizing WPL to construct, own and operate a 17.5 MW natural gas-fired EGU using Reciprocating Internal Combustion Engine (RICE) technology, at the site of its Riverside Energy Center.
In April 2025, WPL filed a CA application with the PSCW for approval to construct, own and operate the Bent Tree North EGU, an approximate 153 MW wind farm. A decision from the PSCW is currently expected in the second quarter of 2026.
In May 2025, the PSCW issued an order authorizing WPL to refurbish the Bent Tree wind farm.
In May 2025, IPL filed a certificate of public convenience, use and necessity (GCU Certificate) application with the IUC for approval to construct, own and operate up to 75 MW of energy storage at the site of its Golden Plains wind farm. A decision from the IUC is currently expected in the fourth quarter of 2025.
In May 2025, IPL filed a GCU Certificate application with the IUC for approval to construct, own and operate up to 75 MW of energy storage at the site of its Whispering Willow - North wind farm. A decision from the IUC is currently expected in the fourth quarter of 2025.
In June 2025, the IUC issued an order authorizing IPL to construct, own and operate the Cedar River Generating Station, a 94 MW natural gas-fired EGU using RICE technology, at the site of its Prairie Creek Generating Station.
In June 2025, the PSCW issued an order authorizing WPL to construct, own and operate an approximately 20 MW compressed carbon dioxide-based long-duration energy storage system at the site of its Columbia Energy Center.
In July 2025, IPL filed for advance rate-making principles with the IUC for up to 1,000 MW of new wind generation in Iowa. The advance rate-making principles filing included requests for a fixed cost cap of $3,020/kilowatt, including allowance for funds used during construction and transmission upgrade costs among other costs, and a return on common equity of 11.25%. A decision from the IUC is currently expected in the first quarter of 2026.
In July 2025, the IUC issued an order authorizing IPL to construct, own and operate up to 150 MW of energy storage at the site of its retired Lansing Generating Station.
In July 2025, WPL completed construction of approximately 100 MW of energy storage at the site of its Grant County solar facility.

Rate Matters:
In March 2025, WPL filed a retail electric and gas rate review with the PSCW for the 2026/2027 forward-looking Test Period. The key drivers for the filing include revenue requirement impacts of increasing electric and gas rate base, including wind refurbishment projects, energy storage, existing natural gas-fired EGU improvements, solar generation costs incurred that exceed the construction cost estimates previously approved by the PSCW, and electric and gas distribution investments. The filing requested approval for WPL to implement increases in annual rates for its retail electric and gas customers of $120 million and $9 million in 2026, respectively, with any granted rate changes expected to be effective on January 1, 2026. WPL’s filing also requested approval to implement an additional increase in annual rates for its retail electric and gas customers of $82 million and $5 million in 2027, respectively, with any granted rate changes expected to be effective on January 1, 2027. WPL also requested a return on common equity of 9.9% and to implement a common equity component of its regulatory capital structure of 55.5% in 2026 and 55.3% in 2027. WPL’s filing also requested an extension, with certain modifications, of its current earnings sharing mechanism through 2027, including deferral of a portion of its earnings if its annual regulatory return on common equity exceeds 10.15% during the 2026/2027 Test Period (deferral of 50% of its excess earnings between 10.15% and 10.65%, and 100% of any excess earnings above 10.65%). A decision from the PSCW is currently expected by the end of 2025.
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Growing Customer Demand:
WPL has entered into an electric service agreement with a new customer, who currently expects to build a data center at the Beaver Dam Commerce Park in Beaver Dam, Wisconsin in WPL’s service territory. The actual timing and amount of increases in WPL’s load are subject to various factors, including interconnections and actual customer demand, and any executed or future agreements with customers are not expected to result in immediate increases in load. IPL’s and WPL’s currently executed electric service agreements include aggregate, maximum demands of approximately 2.1 gigawatts.
In May 2025, the IUC issued an order, with certain conditions, approving individual customer rates associated with certain of the data centers expected to be constructed in IPL’s service territory. In June 2025 and April 2025, IPL and WPL filed requests with the IUC and PSCW, respectively, for approval of the individual customer rates associated with certain of the data centers expected to be constructed in their service territories, with decisions from the IUC and PSCW currently expected by the end of the third quarter of 2025.

Environmental Matters and Stewardship:
In March 2025, the EPA announced it expects to initiate a formal reconsideration of various environmental regulations and programs, including the Cross-State Air Pollution Rule and Effluent Limitation Guidelines. In June 2025, the EPA proposed to repeal Clean Air Act Sections 111(b) and 111(d). In July 2025, the EPA proposed to repeal its 2009 ruling that found GHG contributes to climate change and gave it authority to regulate GHG under the Clean Air Act. The EPA also expects to expedite review of state programs to delegate implementation of the Coal Combustion Residuals Rule and reconsider compliance deadlines. Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these matters, including resolution of ongoing and potential litigation.
Alliant Energy’s current voluntary environmental stewardship goals include the following:
By 2030, reduce GHG emissions from its utility operations by 50% from 2005 levels, reduce its electric utility water supply by 75% from 2005 levels and electrify 100% of its owned light-duty fleet vehicles.
By 2040, eliminate all coal-fired EGUs from its generating fleet.
By 2050, aspire to achieve net-zero GHG emissions from its utility operations.
Alliant Energy’s aspirational GHG goal includes EPA reportable emissions based on applicable regulatory compliance requirements for carbon dioxide, methane and nitrous oxide from its owned fossil-fueled EGUs and distribution of natural gas. Alliant Energy’s voluntary environmental stewardship goals may be revised, or their achievement may be delayed, based on increasing customer energy needs, reliability and resource adequacy requirements, and tax policy changes, and the ability to achieve these goals is subject to various additional risk factors included in the 2024 Form 10-K. These goals are not meant to be considered guidance.

Legislative Matters:
In July 2025, the One Big Beautiful Bill Act was enacted, which modifies various clean energy tax credits under the Inflation Reduction Act of 2022, including production tax credits and investment tax credits. The most significant provisions of the new legislation for Alliant Energy, IPL and WPL relate to the accelerated phase out of clean energy tax credits for eligible projects for which construction begins more than 12 months after the date of enactment or for projects placed in service after 2027, and restricted access to clean energy tax credits for projects that begin construction after 2025 and receive impermissible amounts of construction support from entities with ties to certain foreign countries, including China. Additionally, in July 2025, the Presidential Administration directed the U.S. Department of the Treasury to strictly enforce the termination of clean energy tax credits, including issuing new and revised guidance by September 2025, to ensure that requirements concerning the beginning of construction are not circumvented. Refer to “2025 Highlights” for discussion of Alliant Energy’s, IPL’s and WPL’s current plans to develop and/or acquire new clean energy resources. Alliant Energy, IPL and WPL currently expect these clean energy projects would continue to be eligible for clean energy tax credits. If these clean energy projects do not begin construction within the anticipated timeframes or fail to meet other eligibility requirements, the amount of clean energy tax credits could be significantly reduced, which could adversely impact Alliant Energy’s, IPL’s and WPL’s financial condition and results of operations.

Financings:
Refer to “Results of Operations” for discussion of expected future issuances and retirements of long-term debt in 2025.
In April 2025, WPL submitted an application to the U.S. Army Corps of Engineers for up to $45 million in loans through the Corps Water Infrastructure Financing Program. If finalized, such loans would provide low interest financing for various proposed safety projects at WPL’s Kilbourn and Prairie du Sac hydro EGUs.

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RESULTS OF OPERATIONS

Financial Results Overview - The table below includes diluted EPS for Utilities and Corporate Services, ATC Holdings, and Non-utility and Parent, which are non-GAAP financial measures. Alliant Energy believes these non-GAAP financial measures are useful to investors because they facilitate an understanding of performance and trends, and provide additional information about Alliant Energy’s operations on a basis consistent with the measures that management uses to manage its operations and evaluate its performance. Alliant Energy’s net income and EPS attributable to Alliant Energy common shareowners for the three months ended June 30 were as follows (dollars in millions, except per share amounts):
20252024
Income (Loss)EPSIncome (Loss)EPS
Utilities and Corporate Services$190$0.74$85$0.33
ATC Holdings100.0490.04
Non-utility and Parent(26)(0.10)(7)(0.03)
Alliant Energy Consolidated$174$0.68$87$0.34

Alliant Energy’s Utilities and Corporate Services net income increased by $105 million for the three-month period, primarily due to higher revenue requirements from IPL’s and WPL’s capital investments, an asset valuation charge in 2024 for IPL’s retired Lansing Generating Station, an ARO charge in 2024 allocated to the steam business at IPL due to the revised Coal Combustion Residuals Rule, and estimated temperature impacts on retail electric and gas sales. These items were partially offset by higher depreciation and financing expenses.

Alliant Energy’s Non-utility and Parent net income decreased $19 million for the three-month period, primarily due to lower equity income from corporate venture investments, higher financing expense and the timing of income taxes.

Net Income Variances - The following items contributed to increased (decreased) net income for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):
Three MonthsSix Months
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Revenues:
Changes in electric utility (Refer to details below)
$62$14$48$123$53$70
Changes in gas utility (Refer to details below)
77431033
Changes in other utility12(1)11
Changes in non-utility(3)(4)
Changes in total revenues67165416364103
Operating expenses:
Changes in electric production fuel and purchased power (Refer to details below)
(12)8(20)(24)9(32)
Changes in electric transmission service (Refer to details below)
(4)(1)(2)(8)(5)(3)
Changes in cost of gas sold (Refer to details below)
(5)(5)(28)(4)(24)
Asset valuation charge for IPL’s Lansing Generating Station in 2024 (Refer to Note 2 for details)
60606060
Changes in other operation and maintenance (Refer to details below)
918(5)918(9)
Changes in depreciation and amortization (Higher primarily due to solar generation placed in service in 2024 and updated electric depreciation rates for IPL effective October 1, 2024)(20)(18)(3)(44)(37)(5)
Changes in taxes other than income taxes(2)(1)(1)(1)1(1)
Changes in total operating expenses2666(36)(36)42(74)
Changes in operating income93821812710629
Other income and deductions:
Changes in interest expense (Higher primarily due to financings completed in 2024 and 2025)(16)(10)(2)(28)(15)(4)
Changes in equity income from unconsolidated investments, net (Refer to Note 4 for details)
(5)(8)
Changes in allowance for funds used during construction 422312
Changes in Other12(3)2(3)
Changes in total other income and deductions(16)(6)(3)(33)(12)(5)
Changes in income before income taxes777615949424
Changes in income taxes (Refer to Note 8 for details)
1048483418
Changes in net income$87$80$23$142$128$42

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Electric and Gas Revenues and Sales Summary - Electric and gas revenues (in millions), and MWh and Dth sales (in thousands), for the three and six months ended June 30 were as follows:
Alliant EnergyElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20252024202520242025202420252024
Three Months
Retail$746$7195,9265,948$64$596,1145,730
Sales for resale:
Wholesale4943651653N/AN/AN/AN/A
Bulk power and other43131,1761,087N/AN/AN/AN/A
Transportation/Other13141414121027,15929,102
$851$7897,7677,702$76$6933,27334,832
Six Months
Retail$1,518$1,42512,10011,937$290$25129,93625,848
Sales for resale:
Wholesale97891,3421,333N/AN/AN/AN/A
Bulk power and other69342,5542,757N/AN/AN/AN/A
Transportation/Other19322829262258,16563,009
$1,703$1,58016,02416,056$316$27388,10188,857
IPLElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20252024202520242025202420252024
Three Months
Retail$395$3873,2863,291$33$342,6672,679
Sales for resale:
Wholesale1413161173N/AN/AN/AN/A
Bulk power and other1(2)301205N/AN/AN/AN/A
Transportation/Other86887610,2959,590
$418$4043,7563,677$40$4012,96212,269
Six Months
Retail$804$7626,7246,656$142$13514,43912,885
Sales for resale:
Wholesale2826343356N/AN/AN/AN/A
Bulk power and other2(5)697529N/AN/AN/AN/A
Transportation/Other14121616161322,36621,284
$848$7957,7807,557$158$14836,80534,169
WPLElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20252024202520242025202420252024
Three Months
Retail$351$3322,6402,657$31$253,4473,051
Sales for resale:
Wholesale3530490480N/AN/AN/AN/A
Bulk power and other4215875882N/AN/AN/AN/A
Transportation/Other58665416,86419,512
$433$3854,0114,025$36$2920,31122,563
Six Months
Retail$714$6635,3765,281$148$11615,49712,963
Sales for resale:
Wholesale6963999977N/AN/AN/AN/A
Bulk power and other67391,8572,228N/AN/AN/AN/A
Transportation/Other520121310935,79941,725
$855$7858,2448,499$158$12551,29654,688

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Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes were unchanged and increased 1% for the three and six months ended June 30, 2025, respectively, compared to the same periods in 2024, primarily due to changes in temperatures. Alliant Energy’s retail gas sales volumes increased 7% and 16% for the three and six months ended June 30, 2025, respectively, compared to the same periods in 2024, primarily due to changes in temperatures.

Estimated increases (decreases) to operating income from the impacts of temperatures for the three and six months ended June 30 were as follows (in millions):
ElectricGas
Three MonthsSix Months Three MonthsSix Months
20252024Change20252024Change20252024Change20252024Change
IPL$4$1$3$—($8)$8($1)($1)$—($3)($7)$4
WPL3(2)5(12)12(2)2(1)(7)6
Total Alliant Energy$7($1)$8$—($20)$20($1)($3)$2($4)($14)$10

Electric Sales for Resale - Bulk Power and Other - Bulk power and other volume changes were due to changes in sales in the wholesale energy markets operated by MISO. These changes are impacted by several factors, including the availability and dispatch of Alliant Energy’s EGUs and electricity demand within these wholesale energy markets. Changes in bulk power and other revenues were largely offset by changes in fuel-related costs, and therefore did not have a significant impact on operating income.

Gas Transportation/Other - Gas transportation/other sales volume changes were largely due to changes in the gas volumes supplied to Alliant Energy’s natural gas-fired EGUs caused by the availability and dispatch of such EGUs.

Electric Utility Revenue Variances - The following items contributed to increased (decreased) electric utility revenues for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):
Three MonthsSix Months
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher revenue requirements (a)(b)$94$79$15$202$172$30
Higher sales for resale bulk power and other revenues (c)3032735728
Estimated changes in sales volumes caused by temperatures83520812
Changes in WPL electric fuel-related costs, net of recoveries (d)111166
Lower revenues at IPL due to credits on customers’ bills related to production tax credits through its fuel-related cost recovery mechanism (offset by changes in income taxes) (a)(38)(38)(89)(89)
Lower revenues at IPL due to credits on customers’ bills through the tax benefit rider in 2025 (partially offset by changes in income taxes) (a)(16)(16)(34)(34)
Higher (lower) revenues primarily due to changes in retail electric fuel-related costs (Refer to Electric Production Fuel and Purchased Power Expenses Variances below)
(25)(18)(7)(14)(18)4
Other(2)1(3)(3)7(10)
$62$14$48$123$53$70

(a)In September 2024, the IUC issued an order authorizing an annual base rate increase of $185 million for IPL’s retail electric customers, with customers receiving partially offsetting credits for the first 12 months through a tax benefit rider, for the October 2024 through September 2025 forward-looking Test Period. Rate changes were effective October 1, 2024, which reflect revenue requirement impacts of increasing electric rate base including investments in solar generation, updated depreciation rates, and certain incremental costs incurred resulting from the 2020 derecho windstorm. In addition, effective October 1, 2024, IPL’s renewable energy rider was discontinued, and certain production tax credits are credited to IPL’s retail electric customers through IPL’s fuel-related cost recovery mechanism. Credits on IPL’s customers’ bills have been and are expected to be offset by a reduction in income tax expense.
(b)In December 2023, the PSCW issued an order authorizing an annual base rate increase of $60 million for WPL’s retail electric customers, covering the 2025 forward-looking Test Period, which reflects revenue requirement impacts of increasing electric rate base including investments in solar generation and energy storage.
(c)Alliant Energy’s and WPL’s sales for resale bulk power and other revenues increased primarily due to higher prices for electricity and capacity sold by WPL to MISO wholesale energy markets. These changes were largely offset by changes in fuel-related costs.
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(d)WPL’s cost recovery mechanism for retail fuel-related expenses supports deferrals of amounts that fall outside an approved fuel monitoring range of forecasted fuel-related expenses determined by the PSCW each year. The difference between revenue collected and actual fuel-related expenses incurred within the fuel monitoring range increases or decreases Alliant Energy’s and WPL’s electric utility revenues. WPL estimates the increase (decrease) to electric utility revenues from amounts within the fuel monitoring range were approximately $6 million and $2 million for the three and six months ended June 30, 2025, respectively, compared to ($5) million and ($4) million for the three and six months ended June 30, 2024, respectively.

Gas Utility Revenue Variances - The following items contributed to increased (decreased) gas utility revenues for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):
Three MonthsSix Months
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher revenues due to changes in gas costs (Refer to Cost of Gas Sold Expense Variances below)
$5$—$5$28$4$24
Estimated changes in sales volumes caused by temperatures221046
Higher revenue requirements (a)1155
Other(1)(1)(3)3
$7$—$7$43$10$33

(a)In September 2024, the IUC issued an order authorizing an annual base rate increase of $10 million for IPL’s retail gas customers, for the October 2024 through September 2025 forward-looking Test Period. Rate changes were effective October 1, 2024, which reflect revenue requirement impacts of increasing gas rate base.

Electric Production Fuel and Purchased Power Expenses Variances - The following items contributed to (increased) decreased electric production fuel and purchased power expenses for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):
Three MonthsSix Months
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher electric production fuel costs (a)($21)($12)($9)($27)($17)($10)
Lower (higher) purchased power expense (b)422(10)4(14)
Changes in regulatory recovery of retail electric fuel-related costs819(11)1322(9)
Other(3)(1)(2)1
($12)$8($20)($24)$9($32)

(a)Electric production fuel costs increased for the three and six months ended June 30, 2025, compared to the same periods in 2024, primarily due to higher coal volumes due to higher dispatch of coal-fired EGUs and higher natural gas prices, partially offset by lower natural gas volumes due to lower dispatch of natural gas-fired EGUs.
(b)Purchased power expense increased for the six months ended June 30, 2025 compared to the same period in 2024, primarily due to higher prices for electricity purchased at WPL.

Electric Transmission Service Expense Variances - The following items contributed to (increased) decreased electric transmission service expense for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):
Three MonthsSix Months
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Changes in regulatory recovery for the difference between actual electric transmission service costs and those costs used to determine rates$4$1$3$7$1$6
Other (primarily due to changes in transmission service costs provided by third parties)(8)(2)(5)(15)(6)(9)
($4)($1)($2)($8)($5)($3)

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Cost of Gas Sold Expense Variances - The following items contributed to (increased) decreased cost of gas sold expense for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):
Three MonthsSix Months
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher retail gas volumes and changes in natural gas prices($10)($1)($9)($22)($6)($16)
Changes in the regulatory recovery of gas costs514(6)2(8)
($5)$—($5)($28)($4)($24)

Other Operation and Maintenance Expenses Variances - The following items contributed to (increased) decreased other operation and maintenance expenses for the three and six months ended June 30, 2025 compared to the same periods in 2024 (in millions):
Three MonthsSix Months
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
ARO charge in 2024 for steam assets at IPL (Refer to Note 1(c) for details)
$20$20$—$20$20$—
Other (primarily due to higher generation expense)(11)(2)(5)(11)(2)(9)
$9$18($5)$9$18($9)

Other Future Considerations - In addition to items discussed in this report, the following key items could impact Alliant Energy’s, IPL’s and WPL’s future financial condition or results of operations:
Financing Plans - Alliant Energy currently expects to issue up to $1.3 billion of common stock in aggregate from 2026 through 2028 through the distribution agreement that was executed in May 2025, and up to $25 million of common stock annually through its Shareowner Direct Plan in 2025 through 2028. For the remainder of 2025, IPL and WPL currently expect to issue up to $400 million and $300 million, respectively, of long-term debt, and AEF and/or Alliant Energy at the parent company level expect to issue up to $725 million of long-term debt in aggregate. IPL has $250 million of long-term debt maturing in August 2025.

LIQUIDITY AND CAPITAL RESOURCES

The liquidity and capital resources summary included in the 2024 Form 10-K has not changed materially, except as described below.

Liquidity Position - At June 30, 2025, Alliant Energy had $329 million of cash and cash equivalents, $1,008 million ($550 million at the parent company, $350 million at IPL and $108 million at WPL) of available capacity under the single revolving credit facility and $4 million of available capacity at IPL under its sales of accounts receivable program.

Capital Structure - Financial capital structures at June 30, 2025 were as follows (Long-term Debt (including current maturities) (LD); Short-term Debt (SD); Common Equity (CE)):
636637638
Cash Flows - Selected information from the cash flows statements was as follows (in millions):
Alliant EnergyIPLWPL
202520242025202420252024
Cash, cash equivalents and restricted cash, January 1$81$63$29$53$51$7
Cash flows from (used for):
Operating activities492562108147337391
Investing activities(894)(533)(441)(209)(362)(247)
Financing activities650150818(16)(71)
Net increase (decrease)24830175(44)(41)73
Cash, cash equivalents and restricted cash, June 30
$329$93$204$9$10$80

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Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the six months ended June 30, 2025 compared to the same period in 2024 (in millions):
Alliant EnergyIPLWPL
Lower collections from IPL’s retail customers due to credits on customers’ bills related to production tax credits through its fuel-related cost recovery mechanism($89)($89)$—
Lower collections from IPL’s retail customers due to credits on customers’ bills related to the tax benefit rider(34)(34)
Changes in interest payments(32)(12)(12)
Restructuring and voluntary employee separation payments in 2025(25)(11)(12)
Higher collections from IPL’s and WPL’s retail electric and IPL’s gas base rate increases20717730
Increased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales301218
Changes in income taxes paid/received (a)2(24)18
Other (primarily due to other changes in working capital)(129)(58)(96)
($70)($39)($54)

(a)Refer to the cash flows statements for details of renewable tax credits transferred to other corporate taxpayers during the six months ended June 30, 2025 and 2024.

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the six months ended June 30, 2025 compared to the same period in 2024 (in millions):
Alliant EnergyIPLWPL
Proceeds from sales of partial ownership interests in West Riverside in 2024($123)$—($123)
Changes in the amount of cash receipts on sold receivables(108)(108)
(Higher) lower utility construction and acquisition expenditures (a)(106)(128)22
Other(24)4(14)
($361)($232)($115)

(a)Largely due to higher expenditures for IPL’s energy storage, partially offset by lower expenditures for IPL’s and WPL’s solar generation.

Construction and Acquisition Expenditures - Construction and acquisition expenditures and financing plans are reviewed, approved and updated as part of the strategic planning process. Changes may result from a number of reasons, including changes in expected load growth, regulatory requirements, changing legislation, not obtaining favorable and acceptable regulatory approval on certain projects, changing costs of projects due to market conditions and the impact of tariffs, improvements in technology, and improvements to ensure resiliency and reliability of the electric and gas distribution systems. Alliant Energy, IPL and WPL have not yet entered into contractual commitments relating to the majority of their anticipated future construction and acquisition expenditures. As a result, they have some discretion with regard to the level and timing of these expenditures. Construction and acquisition expenditures for 2025 through 2028 are currently anticipated as follows (in millions), which are focused on adding generation to meet growing customer demand for electricity, including expected future data center growth from currently executed electric service agreements, and strengthening the resiliency and reliability of the electric grid, and include renewable generation and energy storage projects, dispatchable gas generation projects, and converting certain coal-fired EGUs to natural gas. Alliant Energy, IPL and WPL are currently evaluating the impacts of tariffs, recently enacted legislation and additional potential large load growth customers on their resource plans, and will update their anticipated construction and acquisition expenditures as needed in the future. Cost estimates represent Alliant Energy’s, IPL’s and WPL’s portion of construction expenditures and exclude allowance for funds used during construction and capitalized interest, if applicable.
Alliant EnergyIPLWPL
202520262027202820252026202720282025202620272028
Generation:
Renewables and energy storage projects$995 $895 $1,125 $1,160 $675 $480 $580 $660 $320 $415 $545 $500 
Gas projects460 740 1,025 885 240 320 615 645 170 385 410 240 
Other145 135 70 65 65 60 30 15 80 75 40 50 
Distribution:
Electric systems595 625 600 580 325 265 250 255 270 360 350 325 
Gas systems100 130 160 105 55 70 90 40 45 60 70 65 
Other215 230 225 245 45 35 45 50 35 30 35 25 
$2,510 $2,755 $3,205 $3,040 $1,405 $1,230 $1,610 $1,665 $920 $1,325 $1,450 $1,205 

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Table of Contents                        
Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the six months ended June 30, 2025 compared to the same period in 2024 (in millions):
Alliant EnergyIPLWPL
Lower payments to retire long-term debt$305$—$—
Higher (lower) net proceeds from issuance of long-term debt193594(297)
Net changes in the amount of commercial paper outstanding157(50)427
Higher (lower) capital contributions from IPL’s and WPL’s parent company, Alliant Energy20(55)
Higher common stock dividends(15)(80)(21)
Other 961
$649$490$55

Common Stock Issuances - Refer to Note 5 for discussion of common stock issuances by Alliant Energy in 2025 and Alliant Energy’s at-the-market offering program. Refer to “Results of Operations” for discussion of expected future issuances of common stock from 2025 through 2028.

Long-term Debt - Refer to Note 6(b) for discussion of AEF’s term loan credit agreements and various issuances and/or retirements of long-term debt by Alliant Energy and IPL in 2025. Refer to “Results of Operations” for discussion of expected future issuances and retirements of long-term debt in 2025.

Impact of Credit Ratings on Liquidity and Collateral Obligations -
Ratings Triggers - In March 2025, Standard & Poor’s Ratings Services changed certain Alliant Energy, IPL and WPL credit ratings and outlooks, which are not expected to have a material impact on Alliant Energy’s, IPL’s and WPL’s liquidity or collateral obligations, and the current credit ratings and outlooks are as follows:
Standard & Poor’s Ratings Services
Alliant Energy:Corporate/issuerBBB+
Commercial paperA-2
Senior unsecured long-term debtBBB
OutlookStable
IPL:Corporate/issuerBBB+
Commercial paperA-2
Senior unsecured long-term debtBBB+
OutlookStable
WPL:Corporate/issuerA-
Commercial paperA-2
Senior unsecured long-term debtA-
OutlookStable

Off-Balance Sheet Arrangements and Certain Financial Commitments - A summary of Alliant Energy’s and IPL’s off-balance sheet arrangements and Alliant Energy’s, IPL’s and WPL’s contractual obligations is included in the 2024 Form 10-K and has not changed materially from the items reported in the 2024 Form 10-K, except for the items described in Notes 3, 6 and 12.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Quantitative and Qualitative Disclosures About Market Risk are reported in the 2024 Form 10-K and have not changed materially.

ITEM 4. CONTROLS AND PROCEDURES

Alliant Energy’s, IPL’s and WPL’s management evaluated, with the participation of each of Alliant Energy’s, IPL’s and WPL’s Chief Executive Officer, Chief Financial Officer and Disclosure Committee, the effectiveness of the design and operation of Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures (as defined in Rule 13a-15(e) of the Securities Exchange Act of 1934, as amended) as of June 30, 2025 pursuant to the requirements of the Securities Exchange Act of 1934, as amended. Based on their evaluation, the Chief Executive Officer and the Chief Financial Officer concluded that Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures were effective as of the quarter ended June 30, 2025.

There was no change in Alliant Energy’s, IPL’s and WPL’s internal control over financial reporting that occurred during the quarter ended June 30, 2025 that has materially affected, or is reasonably likely to materially affect, Alliant Energy’s, IPL’s or WPL’s internal control over financial reporting.

36

Table of Contents                        
PART II. OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

None. SEC regulations require Alliant Energy, IPL and WPL to disclose information about certain proceedings arising under federal, state or local environmental provisions when a governmental authority is a party to the proceedings and such proceedings involve potential monetary sanctions that Alliant Energy, IPL and WPL reasonably believe will exceed a specified threshold. Pursuant to the SEC regulations, Alliant Energy, IPL and WPL use a threshold of $1 million for purposes of determining whether disclosure of any such proceedings is required. Applying this threshold, there are no environmental matters to disclose for this period.

ITEM 1A. RISK FACTORS

The risk factors described in Item 1A in the 2024 Form 10-K have not changed materially.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

A summary of Alliant Energy common stock repurchases for the quarter ended June 30, 2025 was as follows:

Total NumberAverage PriceTotal Number of SharesMaximum Number (or Approximate
of SharesPaid PerPurchased as Part ofDollar Value) of Shares That May
PeriodPurchased (a)SharePublicly Announced PlanYet Be Purchased Under the Plan (a)
April 1 through April 306,098$60.59N/A
May 1 through May 312,91861.71N/A
June 1 through June 30860.51N/A
9,02460.95

(a)All shares were purchased on the open market and held in a rabbi trust under the Alliant Energy Deferred Compensation Plan. There is no limit on the number of shares of Alliant Energy common stock that may be held under the Deferred Compensation Plan, which currently does not have an expiration date.

ITEM 5. OTHER INFORMATION

(c)During the quarter ended June 30, 2025, no director or officer of Alliant Energy, IPL or WPL adopted or terminated a Rule 10b5-1 trading arrangement or non-Rule 10b5-1 trading arrangement, as each term is defined in Item 408(a) of Regulation S-K.

37

Table of Contents                        
ITEM 6. EXHIBITS

The following Exhibits are filed herewith or incorporated herein by reference.
Exhibit NumberDescription
4.1
Indenture, dated as of May 15, 2025, between Alliant Energy and The Bank of New York Mellon Trust Company, N.A., as trustee (incorporated by reference to Exhibit 4.1 to Alliant Energys Form 8-K, filed May 15, 2025 (File No. 1-9894))
4.2
Officer’s Certificate, dated as of May 19, 2025, creating IPL’s 5.600% Senior Debentures due June 29, 2035 (incorporated by reference to Exhibit 4.1 to IPL’s Form 8-K, filed May 19, 2025 (File No. 1-4117))
31.1
Certification of the Chief Executive Officer for Alliant Energy
31.2
Certification of the Chief Financial Officer for Alliant Energy
31.3
Certification of the Chief Executive Officer for IPL
31.4
Certification of the Chief Financial Officer for IPL
31.5
Certification of the Chief Executive Officer for WPL
31.6
Certification of the Chief Financial Officer for WPL
32.1
Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for Alliant Energy
32.2
Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for IPL
32.3
Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for WPL
101.INSInline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
101.SCHInline XBRL Taxonomy Extension Schema Document
101.CALInline XBRL Taxonomy Extension Calculation Linkbase Document
101.LABInline XBRL Taxonomy Extension Label Linkbase Document
101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document
101.DEFInline XBRL Taxonomy Extension Definition Linkbase Document
104Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company have each duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized on the 8th day of August 2025.

ALLIANT ENERGY CORPORATION
Registrant
By: /s/ Dylan M. Syse
Chief Accounting Officer and Controller
Dylan M. Syse(Principal Accounting Officer and Authorized Signatory)
INTERSTATE POWER AND LIGHT COMPANY
Registrant
By: /s/ Dylan M. Syse
Chief Accounting Officer and Controller
Dylan M. Syse(Principal Accounting Officer and Authorized Signatory)
WISCONSIN POWER AND LIGHT COMPANY
Registrant
By: /s/ Dylan M. Syse
Chief Accounting Officer and Controller
Dylan M. Syse(Principal Accounting Officer and Authorized Signatory)

38

FAQ

What were Alliant Energy's (LNT) consolidated revenues and net income for Q2 2025?

Consolidated revenues were $961 million and net income attributable to common shareowners was $174 million for Q2 2025.

How did Alliant Energy's EPS change year-over-year in Q2 2025?

Diluted EPS increased to $0.68 in Q2 2025 from $0.34 in Q2 2024.

What is Alliant Energy's cash position and total assets as of June 30, 2025?

Cash and cash equivalents were $329 million and total assets were $23,750 million at June 30, 2025.

How much debt does Alliant Energy have and are there near-term maturities?

Long-term debt, net (excluding current portion) was $9,642 million and current maturities of long-term debt were $1,373 million as of June 30, 2025.

What were Alliant Energy's six-month capital expenditures and investing cash flows in 2025?

Construction and acquisition expenditures for the utility business were $976 million and net cash used for investing activities was $894 million for the six months ended June 30, 2025.

Did operating cash flow improve for the six months ended June 30, 2025?

No. Net cash flows from operating activities were $492 million for the six months ended June 30, 2025, down from $562 million in 2024.
Alliant Energy Corp

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