Filed by MFS Municipal Income Trust
pursuant to Rule 425 under the Securities Act of
1933
and deemed filed pursuant to Rule 14a-12
under the Securities Exchange Act of 1934
Subject Companies:
MFS High Income Municipal Trust
File No.: 811-05754
MFS Investment Grade Municipal Trust
File No.: 811-05785
Date: April 2, 2026

For Immediate Release Media Contacts: Dan
Flaherty, +1 617.954.4256
For Shareholders/Advisors: Brian
Mastrullo, +1 617.954.7940
MFS MUNICIPAL CLOSED-END FUNDS ANNOUNCE ADJOURNMENT
OF
SPECIAL SHAREHOLDER MEETINGS
BOSTON (April 2, 2026) – MFS Investment Management
(“MFS”) announced today an adjournment of the special meeting of shareholders of MFS High Income Municipal Trust (NYSE: CXE)
and MFS Investment Grade Municipal Trust (NYSE: CXH) (each a “Target Fund” and collectively, the “Target Funds”)
held on April 2, 2026 (each a “Meeting” and collectively, the “Meetings”).
Each Meeting is adjourned to April 7, 2026, at 11:00 a.m. Eastern
Time.
The Meetings were adjourned to allow for the solicitation of additional
shareholder votes relating to a proposal that each Target Fund’s shareholders approve an Agreement and Plan of Reorganization between
each Target Fund and the MFS Municipal Income Trust (NYSE: MFM) (the “Surviving Fund”) (each a “Reorganization”
and collectively, the “Reorganizations”).
The Reorganizations
On December 10, 2025, the Board of Trustees (the “Board”)
of each Target Fund unanimously approved the Reorganizations. Shareholders of each Target Fund as of December 11, 2025, were mailed a
prospectus/proxy statement in early February 2026, providing additional information about each Reorganization and the factors considered
by each Target Fund’s Board in approving the relevant Target Fund’s Reorganization. Each Target Fund’s Board determined
that the Reorganization of that Target Fund into the Surviving Fund is in the best interests of the Target Fund’s shareholders and
recommends shareholders vote in favor of their Target Fund’s Reorganization.
Conditional Tender Offer for CXH
On March 4, 2026, MFS announced that the Board authorized CXH
to conduct a conditional cash tender offer for up to 50% of outstanding common shares of CXH at a price equal to 99% of CXH’s net
asset value (the “Tender Offer”). The Tender Offer will be subject to certain conditions that will be set forth in a tender
offer statement on Schedule TO, which will be filed with the U.S. Securities and Exchange

Commission, and an offer to purchase, which will be mailed
to shareholders of CXH as of the record date upon commencement of the Tender Offer. Among other conditions, the commencement of the Tender
Offer is contingent upon CXH receiving the necessary shareholder vote in favor of its Reorganization. As such, the Tender Offer will not
commence unless and until the requisite shareholder vote is received at the adjourned special meeting of shareholders for CXH scheduled
for April 7, 2026, or any further adjournment thereof.
Appointment of Aberdeen as Investment Adviser, the Election
of Five New Trustees, and Issuance of Additional Common Shares of the Surviving Fund
On December 10, 2025, the Board of the Surviving Fund unanimously
approved (i) a new investment management agreement with Aberdeen, the US Subsidiary of Aberdeen Investments,
to serve as the investment adviser to the Surviving Fund following the consummation of the Reorganizations, (ii) the nomination of five
new trustees to serve as the Surviving Fund’s board of trustees following the consummation of the Reorganizations, and (iii) the
issuance of additional common shares of the Surviving Fund to accommodate the Reorganizations. Shareholders of the Surviving Fund as of
December 11, 2025, were mailed a proxy statement in early February 2026, providing additional information and soliciting a vote in favor
of each proposal, all of which were recommended by the Surviving Fund’s Board. On April 2, 2026, shareholders of the Surviving Fund
approved each of the above discussed proposals.
Cautionary Statement Regarding Forward-Looking Statements
This press release may contain statements regarding plans and expectations
for the future that constitute forward-looking statements within The Private Securities Litigation Reform Act of 1995. All statements
other than statements of historical fact are forward-looking and can be identified by the use of words such as "may," "will,"
"expect," "anticipate," "estimate," "believe," "continue," or other similar words. Such
forward-looking statements are based on the fund's current plans and expectations, are not guarantees of future results or performance,
and are subject to risks and uncertainties that could cause actual results to differ materially from those described in the forward-looking
statements. All forward-looking statements are as of the date of this release only; the funds undertake no obligation to update or review
any forward-looking statements. You are urged to carefully consider all such factors.
About the Funds
The funds are closed-end investment company products advised
by MFS Investment Management. Closed-end funds, unlike open-end funds, are not continuously offered. There is a one-time public offering
and once issued, common shares of the funds are bought and sold in the open market through a stock exchange. Shares may trade at a discount
to the net asset value per share. Shares of the funds are not FDIC-insured and are not deposits or other obligations of, or guaranteed
by, any bank. Shares of the funds involve investment risk, including possible loss of principal.
About MFS Investment Management
In 1924, MFS launched the first US open-end mutual fund, opening
the door to the markets for millions of everyday investors. Today, as a full-service global investment manager serving financial advisors,
intermediaries and institutional clients, MFS still serves a single purpose: to create long term value for

clients by allocating capital responsibly. That takes our powerful
investment approach combining collective expertise, thoughtful risk management and long-term discipline. Supported by our culture of shared
values and collaboration, our teams of diverse thinkers actively debate ideas and assess material risks to uncover what we believe are
the best investment opportunities in the market. As of February 28, 2026, MFS had approximately US$669.8 billion in assets under management.
MFS Investment Management
111 Huntington Ave., Boston, MA 02199
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