8-K

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):  January 30, 2026

CAPITAL SOUTHWEST CORPORATION

(Exact Name Of Registrant As Specified In Charter)

8333 Douglas Avenue, Suite 1100

Dallas, Texas 75225

(Address of Principal Executive Offices) (Zip Code)

Registrant’s telephone number, including area code: (214) 238-5700

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 (see General Instruction A.2. below):

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

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).

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. ☐

Item 7.01 Regulation FD Disclosure

On January 30, 2026, Capital Southwest Corporation (the "Company") issued a press release announcing the tax treatment of its 2025 dividends, a copy of which has been furnished as Exhibit 99.1 hereto and is incorporated by reference herein. The Company paid dividends totaling $2.56 per share that are attributable to the tax year ended December 31, 2025, which were comprised of 100.00% ordinary income.

The information set forth under this Item 7.01, including Exhibit 99.1, is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference into any filing made by the Company under the Securities Act of 1933, as amended, or the Exchange Act.

Item 9.01 Financial Statements and Exhibits.

(d)          Exhibits

SIGNATURES

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.

Dated: January 30, 2026

Document

Exhibit 99.1

Capital Southwest Announces U.S. Federal Income Tax Treatment of 2025 Dividends

Dallas, Texas - January 30, 2026 - Capital Southwest Corporation (“Capital Southwest” or the “Company”) (Nasdaq: CSWC), an internally managed business development company focused on providing flexible financing solutions to support the acquisition and growth of middle market businesses, announced today the U.S. federal income tax treatment of its 2025 dividends.

U.S. Federal Income Tax Treatment of 2025 Dividends

Capital Southwest paid dividends totaling $2.56 per share that are attributable to the tax year ended December 31, 2025, which were comprised of 100.00% ordinary income, including net short-term capital gains. Further, the ordinary income was 73.89% taxed as ordinary income and 26.11% taxed as qualified dividends. The Company has posted information regarding the U.S. federal income tax characteristics of its dividends that are attributable to 2025 on its website (http://www.capitalsouthwest.com/tax-information).

The amounts shown in the table below represent the final classification of the Company’s 2025 dividends. This information supersedes any estimated information you may have received during the tax year ended December 31, 2025. The 2025 dividends are classified as follows:

(i) Form 1099-DIV Box 1a includes the combined amounts of the columns "Ordinary Dividend Per Share" and "Qualified Dividends Per Share," contained within table above.

(ii) The portion of the dividend reported in Box 1a treated as Qualified Dividend is reported on Form 1099-DIV in Box 1b.

(iii) Net Capital Gain Dividend is reported on Form 1099-DIV in Box 2a.

(iv) The Company designates the above percentages of each of the total dividends by payment date as Interest-Related Dividend and Short-Term Capital Gain Dividend in accordance with Sections 871(k) and 881(e) under the Internal Revenue Code (the "Code").

(v) The percentages designate the portion of Capital Southwest's dividends received by Non-U.S. Residents and Foreign Corporation Shareholders that constitute Interest-Related Dividends, Short-Term Capital Gains Dividends, and Net Capital Gain Dividends to total amount of the dividends derived which generally are exempt from U.S. withholding tax for these periods for Non-U.S. Residents and Foreign Corporation Shareholders.

Non-U.S. residents and foreign corporation shareholders ("Non-U.S. Shareholders") in a regulated investment company ("RIC"), such as Capital Southwest, are exempt from U.S. withholding tax on both "interest-related" dividends and short-term capital gains in accordance with Sections 871(k) and 881(e) of the Code. In addition, Non-U.S. Shareholders in a RIC are also exempt from U.S. withholding tax on long-term capital gains. Approximately 82.55% of Capital Southwest’s 2025 dividends relate to interest and short-term capital gains.  See the "Tax Treatment of 2025 Dividends for Non-U.S. Shareholders" posted on the Company's website for more details (http://www.capitalsouthwest.com/tax-information).

Dividends distributed to Non-U.S. Shareholders may have been withheld to pay U.S. federal income tax. Non-U.S. Shareholders should contact their tax advisor with any questions regarding this information, and its application to any claim for refund of taxes paid to the U.S. Internal Revenue Service.

About Capital Southwest

Capital Southwest Corporation (Nasdaq: CSWC) is a Dallas, Texas-based, internally managed business development company with approximately $1.9 billion in investments at fair value as of September 30, 2025. Capital Southwest is a middle market lending firm focused on supporting the acquisition and growth of middle market businesses with $5 million to $50 million investments across the capital structure, including first lien, second lien and non-control equity co-investments. As a public company with a permanent capital base, Capital Southwest has the flexibility to be creative in its financing solutions and to invest to support the growth of its portfolio companies over long periods of time.

Investor Relations Contact:

Michael S. Sarner, President and Chief Executive Officer

214-884-3829