Entry into a Material Definitive Agreement. On August 16, 2022, Marten Transport, Ltd. (“Marten”) entered into a credit agreement (the “Credit Agreement”) with U.S. Bank National Association, as agent (the “Agent”), and certain banks party thereto (the “Banks”). The Credit Agreement provides for a five-year unsecured revolving credit facility in an aggregate principal amount of up to $30 million. Certain subsidiaries of Marten guarantee Marten’s obligations under the Credit Agreement and any…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information described under Item 1.01 “Entry into a Material Definitive Agreement” is incorporated herein by this reference. 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 thereunto duly authorized. MARTEN TRANSPORT, LTD. Dated: August 25, 2026 By /s/ Jame…

Results of Operations and Financial Condition. On July 23, 2026, the company issued a press release announcing financial results for the quarter ended June 30, 2026. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated July 23, 2026 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue, with both amounts n…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information described under Item 1.01 “Entry into a Material Definitive Agreement” is incorporated herein by this reference. Section 9 – Financial Statements and Exhibits

Entry into a Material Definitive Agreement. On August 16, 2022, Marten Transport, Ltd. (“Marten”) entered into a credit agreement (the “Credit Agreement”) with U.S. Bank National Association, as agent (the “Agent”), and certain banks party thereto (the “Banks”). The Credit Agreement provides for a five-year unsecured revolving credit facility in an aggregate principal amount of up to $30 million. Certain subsidiaries of Marten guarantee Marten’s obligations under the Credit Agreement and any…

The filing details changes in compensation arrangements and incentive plans for executives and non-employee directors.

Results of Operations and Financial Condition. On April 23, 2026, the company issued a press release announcing financial results for the quarter ended March 31, 2026. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated April 23, 2026 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue, with both amount…

Results of Operations and Financial Condition. On January 27, 2026, the company issued a press release announcing financial results for the quarter and year ended December 31, 2025. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated January 27, 2026 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue,…

Results of Operations and Financial Condition. On October 23, 2025, the company issued a press release announcing financial results for the quarter ended September 30, 2025. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated October 23, 2025 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue, with bot…

CEO — Timothy M. Kohl: Timothy M. Kohl, the CEO, is retiring from the company.

CEO — Timothy M. Kohl: The CEO is retiring with a named, long-tenured internal successor (Randolph L. Marten) appointed to take over immediately, indicating an orderly succession rather than a sudden loss of leadership.

Results of Operations and Financial Condition. On July 16, 2025, the company issued a press release announcing financial results for the quarter ended June 30, 2025. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated July 16, 2025 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue, with both amounts n…

The filing discloses changes to executive compensation and equity plan forms, not a change in management personnel or roles.

Results of Operations and Financial Condition. On April 16, 2025, the company issued a press release announcing financial results for the quarter ended March 31, 2025. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated April 16, 2025 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue, with both amount…

Director — Thomas J. Winkel: A director is voluntarily choosing not to seek reelection for personal reasons, which is a standard board turnover event without indication of conflict or operational impact.

Results of Operations and Financial Condition. On January 27, 2025, the company issued a press release announcing financial results for the quarter and year ended December 31, 2024. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated January 27, 2025 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue,…

Results of Operations and Financial Condition. On October 17, 2024, the company issued a press release announcing financial results for the quarter ended September 30, 2024. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated October 17, 2024 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue, with bot…

CFO — James J. Hinnendael: The filing discloses a temporary reduction in executive base salaries as a cost-saving measure, not a change in personnel or management roles.

Results of Operations and Financial Condition. On July 18, 2024, the company issued a press release announcing financial results for the quarter ended June 30, 2024. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated July 18, 2024 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue, with both amounts n…

The filing details the approval of a standard fee schedule and equity grants for non-employee directors, which is a compensation matter rather than a change in management personnel.

Results of Operations and Financial Condition. On April 18, 2024, the company issued a press release announcing financial results for the quarter ended March 31, 2024. Attached hereto as Exhibit 99.1 is a copy of the company’s press release dated April 18, 2024 announcing the company’s financial results for this period. The press release also includes a discussion of operating revenue, net of fuel surcharge revenue; and operating expenses as a percentage of operating revenue, with both amount…