KIRBY CORP

This booklet contains the notice of the Annual Meeting and the Proxy Statement, which contains information about the proposals to be voted on at the meeting, Kirby’s Board of Directors and its committees, and certain executive officers. This year you are being asked to:

Elect three Class I directors;

Ratify the Audit Committee’s selection of KPMG LLP as Kirby’s independent registered public accounting firm for 2026;

Cast an advisory vote on executive compensation;

Approve the Amendment of the 2005 Stock and Incentive Plan; and

Approve the Amendment of the 2000 Nonemployee Director Stock Plan.

General Information

This Proxy Statement is furnished in connection with the solicitation of proxies on behalf of the Board of Directors of Kirby Corporation to be voted at the Annual Meeting of Stockholders to be held on Monday, April 27, 2026, at 10:00 a.m. (CDT). Stockholders of record at the close of business on March 2, 2026, will be able to attend the 2026 Annual Meeting at Kirby’s executive offices located at 55 Waugh Drive, Suite 1100, Houston, Texas 77007.

The mailing address of Kirby’s principal executive offices is P.O. Box 1745, Houston, Texas 77251-1745 and the office number is 713-435-1000.

Whenever we refer in this Proxy Statement to the Annual Meeting, we are also referring to any meeting that results from an adjournment or postponement of the Annual Meeting.

Unless the context requires otherwise, the terms “Kirby,” “the Company,” “our,” “we,” “us,” and similar terms refer to Kirby Corporation, together with its consolidated subsidiaries.