Banco Santander (SAN) details €2.7B share buyback progress

Rhea-AI Filing Summary

Banco Santander reports progress on its previously announced share buyback programme. As of 15 April 2026, the bank has repurchased shares for a cash amount of €2,705,497,424, representing approximately 53.8% of the programme’s maximum investment amount.

These purchases mean the bank has bought back around 16.8% of its outstanding shares as of 2021. Between 8 and 15 April 2026, it acquired 6,000 shares on the XMAD market at weighted average prices between about €10.33 and €10.63 per share.

Key Figures

Buyback cash amount: €2,705,497,424 Share of max buyback budget: 53.8% Shares repurchased vs 2021: 16.8% +3 more

6 metrics

Buyback cash amount €2,705,497,424 Cash spent on buyback as of 15 April 2026

Share of max buyback budget 53.8% Portion of maximum investment amount used

Shares repurchased vs 2021 16.8% Approximate fraction of outstanding shares as of 2021

Shares bought 8–15 April 2026 6,000 shares Own shares repurchased on XMAD in the reported week

Lowest daily weighted price €10.3315 Weighted average price on 13/04/2026

Highest daily weighted price €10.6303 Weighted average price on 15/04/2026

Key Terms

Buyback Programme, inside information, Market Abuse, Commission Delegated Regulation (EU) 2016/1052, +1 more

5 terms

Buyback Programme financial

"relating to the buyback programme of own shares (the “Buyback Programme”)"

inside information regulatory

"Reference is made to our notice of inside information of 4 February 2026"

Information not available to the public that, if known, would likely cause a company’s stock or bonds to rise or fall—for example, undisclosed earnings, deals, product results, or management plans. It matters because trading on that information gives an unfair advantage, can distort market prices, and is typically illegal or subject to strict rules, so investors watch for proper disclosure and compliance to protect fair, transparent markets.

Market Abuse regulatory

"Pursuant to article 5 of Regulation (EU) no. 596/2014 on Market Abuse"

Market abuse is illegal or unethical behavior that distorts the price or fairness of buying and selling financial assets, such as using secret information to trade, spreading false or misleading news, or creating fake buying and selling to give a false impression of demand. It matters to investors because it can cause unfair losses, unreliable prices and legal or reputational fallout; like cheating in a game or tampering with a scale, it destroys confidence that markets reflect true value.

Commission Delegated Regulation (EU) 2016/1052 regulatory

"and articles 2.2 and 2.3 of Commission Delegated Regulation (EU) 2016/1052"

OTHER RELEVANT INFORMATION regulatory

"hereby communicates the following OTHER RELEVANT INFORMATION"

Form 6-K: How Foreign Companies Report to the SEC →

FORM 6-K

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Report of Foreign Issuer

Pursuant to Rule 13a-16 or 15d-16 of

the Securities Exchange Act of 1934

For the month of April, 2026

Commission File Number: 001-12518

Banco Santander, S.A.

(Exact name of registrant as specified in its charter)

Ciudad Grupo Santander

28660 Boadilla del Monte (Madrid) Spain

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

Form 20-F X Form 40-F

Banco Santander, S.A.

TABLE OF CONTENTS

Item
1	Report of Other Relevant Information dated April 16, 2026

Banco Santander, S.A. (the “Bank” or “Banco Santander”), in compliance with the Securities Market legislation, hereby communicates the following:

OTHER RELEVANT INFORMATION

Reference is made to our notice of inside information of 4 February 2026 (official registry number 3077) (the “Buyback Commencement Communication”), relating to the buyback programme of own shares (the “Buyback Programme”) approved by the Board of Directors of Banco Santander.

Pursuant to article 5 of Regulation (EU) no. 596/2014 on Market Abuse of 16 April 2014, and articles 2.2 and 2.3 of Commission Delegated Regulation (EU) 2016/1052, of 8 March 2016, the Bank informs of the transactions carried out over its own shares between 8 and 15 April (both inclusive).

The cash amount of the shares purchased to 15 April 2026 as a result of the execution of the Buyback Programme amounts to 2,705,497,424 Euros, which represents approximately 53.8% of the maximum investment amount of the Buyback Programme. The programme was announced together with its other characteristics through the Buyback Commencement Communication. With these purchases, the Bank has repurchased approximately 16.8% of its outstanding shares as of 2021.

Date	Security	Transaction	Trading venue	Number of shares	Weighted average price (€)
08/04/2026	SAN	Purchase	XMAD	1,000	10.4867
09/04/2026	SAN	Purchase	XMAD	1,000	10.3363
10/04/2026	SAN	Purchase	XMAD	1,000	10.4871
13/04/2026	SAN	Purchase	XMAD	1,000	10.3315
14/04/2026	SAN	Purchase	XMAD	1,000	10.5769
15/04/2026	SAN	Purchase	XMAD	1,000	10.6303
			TOTAL	6,000

Issuer name: Banco Santander, S.A. - LEI 5493006QMFDDMYWIAM13

Reference of the financial instrument: ordinary shares - Code ISIN ES0113900J37

Detailed information of the transactions carried out within the referred period is attached as Annex I.

Boadilla del Monte (Madrid), 16 April 2026

ANNEX I

Detailed information on each of the transactions carried out within the context of the Buy-back Programme between 08/04/2026 and 15/04/2026 (both inclusive)

(https://www.santander.com/content/dam/santander-com/es/documentos/cumplimiento/do-anexo-i-8-a-15-abril-2026-es.pdf)

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

		Banco Santander, S.A.
Date:	April 16, 2026	By:	/s/ Pedro de Mingo Kaminouchi
			Name:	Pedro de Mingo Kaminouchi
			Title:	Head of Corporate Compliance

FAQ

What share buyback progress did Banco Santander (SAN) report in April 2026?

Banco Santander reported that by 15 April 2026 it had repurchased shares for €2,705,497,424 under its ongoing buyback programme. This represents 53.8% of the maximum investment amount approved, marking substantial execution of the previously announced capital return plan.

How much of Banco Santander’s share buyback budget has been used so far?

By 15 April 2026, Banco Santander had used 53.8% of the maximum investment amount in its share buyback programme. The bank spent €2,705,497,424 repurchasing its own shares, reflecting more than half of the authorised cash allocation for this programme.

What portion of Banco Santander (SAN) shares has the buyback retired?

The bank states that its buyback programme has resulted in the repurchase of approximately 16.8% of its outstanding shares as of 2021. This figure reflects cumulative execution of the programme, reducing the historical share count referenced to that 2021 baseline.

What trading activity occurred between 8 and 15 April 2026 in the Banco Santander buyback?

Between 8 and 15 April 2026, Banco Santander bought 6,000 of its own shares on the XMAD market. Daily purchases were 1,000 shares, at weighted average prices ranging from €10.3315 to €10.6303 per share, as part of the broader buyback programme.

On which market were Banco Santander shares repurchased during the reported period?

During the 8–15 April 2026 period, Banco Santander executed its buyback purchases on the XMAD trading venue. Each trading day in that window saw 1,000 shares repurchased, using market transactions in ordinary shares identified by ISIN code ES0113900J37.

What regulatory framework governs Banco Santander’s share buyback programme?

The buyback operates under article 5 of Regulation (EU) 596/2014 on Market Abuse and articles 2.2 and 2.3 of Commission Delegated Regulation (EU) 2016/1052. These rules set conditions for issuer share repurchases, including transparency and market integrity requirements.