Form 8-K

8-K — abrdn National Municipal Income Fund

Accession: 0001104659-26-043922

Filed: 2026-04-16

Period: 2026-04-15

CIK: 0000895574

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — tm2611945d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2611945d1_ex99-1.htm)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of Earliest Event Reported):

April 15, 2026

ABRDN NATIONAL MUNICIPAL INCOME FUND

(Exact name of Registrant as specified in its

charter)

Massachusetts

811-07410

41-173716

(State

or other jurisdiction of incorporation

or organization)

(Commission

File

Number)

(I.R.S.

Employer

Identification No.)

1900 Market Street, Suite 200

Philadelphia, PA

19103

(Address of Principal Executive Offices)

(Zip Code)

(800) 522-5465

(Registrant’s telephone number, including

area code)

Check the appropriate box below if the Form 8-K filing is intended

to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Written

communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

Soliciting

material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

Pre-commencement

communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

Pre-commencement

communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title

of each class

Trading

Symbol(s)

Name

of each exchange on which

registered

Common

Shares of Beneficial Interest

VFL

New

York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth

company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities

Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging

growth company ¨

If an emerging

growth company, indicate by checkmark 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. ¨

Item 8.01. Other Events

On April 15, 2026, the Board of Trustees (the “Board”)

of abrdn National Municipal Income Fund (the “Fund”) approved a change in the Fund’s non-fundamental investment policy

relating to investments in below-investment grade municipal obligations as set forth below. This change will be effective on June 1,

2026.

Current

New

“The

Fund may invest up to 20% of its net assets in Municipal Obligations that are rated below investment grade or that are unrated but

judged by the Investment Manager to be of comparable quality.”

“The

Fund may invest up to 100% of its assets in Municipal Obligations that are rated below investment grade or that are unrated but judged

by the Investment Manager to be of comparable quality.”

All other investment limitations remain unchanged.

Exposure to Below Investment Grade Quality Municipal Obligations

Removing this non-fundamental investment limitation may result in

larger credit exposure and greater investment risk from below investment grade quality Municipal Obligations. In particular, the Fund’s

anticipated larger allocation (initially 30% and between approximately 30% and 50% over time) to below investment grade quality Municipal

Obligations increases the risk from investment in high-yield bonds. The risk for investments in high-yield bonds and other lower-rated

securities is as follows: Investments in high-yield bonds (commonly referred to as “junk bonds”) and other lower-rated securities

will subject the Fund to substantial risk of loss. Investments in high-yield bonds are speculative and issuers of these securities are

generally considered to be less financially secure and less able to repay interest and principal than issuers of investment-grade securities.

Prices of high-yield bonds tend to be very volatile. These securities are less liquid than investment-grade debt securities and may be

difficult to price or sell, particularly in times of negative sentiment toward high-yield securities.

A copy of the press release relating to the changes described above

is attached hereto as Exhibit 99.1.

Item 9.01

Financial Statements and Exhibits.

(d) Exhibits

99.1 Press Release

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

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, hereunto duly authorized.

abrdn National Municipal Income

Fund

Date: April 15, 2026

/s/ Robert Hepp

Name: Robert Hepp

Title: Vice President

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2611945d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

abrdn National Municipal Income Fund (VFL)

Announces Removal of Non-Fundamental Investment Policy Restricting Investments in High-Yield Municipal Securities

(Philadelphia, April 15, 2026) – abrdn National Municipal

Income Fund (NYSE: VFL) announces that the Board of Trustees has approved the removal of a non-fundamental investment policy that restricted

VFL from investing more than 20% of its portfolio in high-yield municipal securities. This change is effective June 1, 2026.

In reaching this decision, the Board considered, among other things,

that removing this non-fundamental investment policy would likely result in higher credit exposure. The Board weighed the modest increase

in credit risk against potential benefits, including expanded diversification, greater earnings, higher distributions, and improved long-term,

risk-adjusted returns. The Board concluded that the broader investment mandate would better position VFL to serve shareholders. Additional

details can be found on VFL's website at the following link: www.aberdeenvfl.com.

Following the effective date of June 1, 2026, while the VFL may

invest in below investment grade securities without limitation, it is expected that VFL will increase its exposure to high-yield securities

in stages, moving to approximately 30% of the portfolio initially, and approximately 30% to 50%, depending on market conditions, over

time.

Important Information

Closed-end funds are traded on the secondary market through one of

the stock exchanges. A fund’s investment return and principal value will fluctuate so that an investor’s shares may be worth

more or less than the original cost. Shares of closed-end funds may trade above (a premium) or below (a discount) the net asset value

(NAV) of the fund’s portfolio. There is no assurance that a fund will achieve its investment objective. Past performance does not

guarantee future results.

The value at which a closed-end fund stock trades on a stock exchange is a function of external market factors that are not under the

control of the Fund’s Board or Investment Advisor. Closed-end fund shares may therefore trade at a premium or a discount to

net asset value at any given time. Shareholders should be aware that a fund trading at a premium to net asset value may not be sustainable,

and a fund’s discount to net asset value can widen as well as narrow. Shareholders of a fund trading at a premium who participate

in that fund’s dividend reinvestment plan should note the reinvestment of distributions may occur at a premium to net asset value.

About Aberdeen Investments

Aberdeen Investments Global is the trade name of Aberdeen's investments

business, herein referred to as “Aberdeen Investments” or “Aberdeen”. In the United States, Aberdeen Investments

refers to the following affiliated, registered investment advisers: abrdn Inc., abrdn Investments Limited, and abrdn Asia Limited.

Aberdeen Investments is one of the world’s

largest asset management firms with extensive experience in managing closed-end funds dating back to the 1980s. As of December 31,

2025, Aberdeen Investments had approximately $525 billion in assets under management.

For More Information Contact:

Aberdeen Investments U.S.

Closed-End Funds

Investor Relations

1-800-522-5465

investor.relations@aberdeenplc.com

abrdn National

Municipal Income Fund | Aberdeen

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