Entry into a Material Definitive Agreement. On August 12, 2026, Wabash National Corporation (the “Company”) entered into a Sixth Amendment to Second Amended and Restated Credit Agreement (the “Amendment”), among the Company, certain of its subsidiaries party thereto as loan parties, the lenders party thereto and Wells Fargo Capital Finance, LLC, as the administrative agent (the “Agent”), which amended the Company’s existing Second Amended and Restated Credit Agreement dated as of December 21,…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information included in

Director — Sudhanshu Priyadarshi: The resignation was not due to a disagreement with the Company or the Board.

Results of Operations and Financial Condition. On July 29, 2026, Wabash National Corporation (the “Company”) issued a press release announcing its financial results for the quarter ended June 30, 2026. A copy of the Company’s press release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. The press release and a teleconference visual presentation are also available on the Company's Investor Relations website at ir.onewabash.com.

Unregistered Sales of Equity Securities. The information set forth under

Entry Into a Material Definitive Agreement. On July 20, 2026, Wabash National Corporation (the “Company”) completed its previously announced private unregistered offering (the “Offering”) of $130 million in aggregate principal amount of 4.00% Convertible Senior Notes due 2032 (the “Initial Notes”). On July 16, 2026, the initial purchasers in the Offering exercised their option to purchase an additional $20 million in aggregate principal amount of the Company’s 4.00% Convertible Senior Notes d…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information set forth under

Entry into a Material Definitive Agreement. On July 14, 2026, Wabash National Corporation (the “Company”) entered into a Fifth Amendment to Second Amended and Restated Credit Agreement (the “Amendment”) among the Company, certain of its subsidiaries as borrowers, certain of its subsidiaries as guarantors, the lenders party thereto and Wells Fargo Capital Finance, LLC, as the administrative agent, which amended the Company’s existing Second Amended and Restated Credit Agreement dated as of Dec…

Other Events. On July 14, 2026, the Company issued a press release relating to the commencement of the Offering. A copy of the press release relating to the Offering is filed as Exhibit 99.2 to this Report and is incorporated by reference herein. Neither this Report nor the press release attached hereto as Exhibit 99.2 constitutes an offer to sell or a solicitation of an offer to buy the Notes, any shares of the Company’s common stock issuable upon conversion of the Notes, or any other securi…

Results of Operations and Financial Condition. On July 14, 2026, the Company announced its intention to offer, subject to market conditions and other factors, convertible senior notes due 2032 (the “Notes”) in a private placement (the “Offering”) to persons reasonably believed to be qualified institutional buyers pursuant to Rule 144A promulgated under the Securities Act of 1933, as amended (the “Securities Act”). In connection with the Offering, the Company provided the disclosure attached a…

Results of Operations and Financial Condition. On May 1, 2026, Wabash National Corporation (the “Company”) issued a press release announcing its financial results for the quarter ended March 31, 2026. A copy of the Company’s press release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. The press release and a teleconference visual presentation are also available on the Company's Investor Relations website at ir.onewabash.com.

Senior Vice President, Chief Growth Officer — Michael N. Pettit: Mr. Pettit is transitioning from his role as Senior Vice President, Chief Growth Officer and will remain in a non-executive consulting capacity until the third quarter of 2026.

Results of Operations and Financial Condition. On February 4, 2026, Wabash National Corporation (the “Company”) issued a press release announcing its financial results for the year and quarter ended December 31, 2025. A copy of the Company’s press release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. The press release and a teleconference visual presentation are also available on the Company’s Investor Relations website at ir.onewabash.com.

Costs Associated with Exit or Disposal Activities. On January 5, 2026, Wabash National Corporation (the “Company”) announced and initiated a plan to idle its facilities in Little Falls, Minnesota and in Goshen, Indiana. The plan includes job reductions of approximately 3 salaried and 53 hourly employees and 21 salaried and 193 hourly employees, respectively, and is expected to be substantially complete by the end of Q2 2026. The total charges associated with this action are expected to be bet…

Forward-Looking Statements This Current Report on Form 8-K (“Current Report”) contains certain forward-looking statements as defined by the Private Securities Litigation Reform Act of 1995. Forward-looking statements convey the Company’s current expectations or forecasts of future events. All statements contained in this Current Report other than statements of historical fact are forward-looking statements. These forward-looking statements include, among other things, all statements regarding…

Results of Operations and Financial Condition. On October 30, 2025, Wabash National Corporation (the “Company”) issued a press release announcing its financial results for the quarter ended September 30, 2025. A copy of the Company’s press release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. The press release and a teleconference visual presentation are also available on the Company's Investor Relations website at ir.onewabash.com.

Other Events. On October 9, 2025, the Company finalized a settlement (the “Settlement”) with the plaintiffs in a lawsuit, Eileen Williams, Elizabeth Perkins, et al. v. Wabash National Corporation, et al., filed in the Circuit Court of the City of St. Louis, Missouri (the “Product Liability Matter”), in which the Company was named as co-defendant. The Product Liability Matter related to a vehicle accident that resulted in two fatalities following a rear-end collision by a passenger vehicle wit…

Results of Operations and Financial Condition. On October 10, 2025, Wabash National Corporation (the "Company") announced certain preliminary results for the quarter ended September 30, 2025. The preliminary results are subject to adjustment and finalization by the Company. There can be no assurance that our final results will not differ from these preliminary estimates. Net sales for the third quarter of 2025 are expected to be $382 million compared to $464 million for the prior year quarter…

Results of Operations and Financial Condition. On July 25, 2025, Wabash National Corporation (the “Company”) issued a press release announcing its financial results for the quarter ended June 30, 2025. A copy of the Company’s press release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. The press release and a teleconference visual presentation are also available on the Company's Investor Relations website at ir.onewabash.com.

Results of Operations and Financial Condition. On April 30, 2025, Wabash National Corporation (the “Company”) issued a press release announcing its financial results for the quarter ended March 31, 2025. A copy of the Company’s press release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. The press release and a teleconference visual presentation are also available on the Company's Investor Relations website at ir.onewabash.com.

Other Events. As previously disclosed in Wabash National Corporation’s (the “Company”) filings with the Securities and Exchange Commission, on (1) October 6, 2020, the Company was named as a co-defendant in a lawsuit, Eileen Williams, Elizabeth Perkins, et al. v. Wabash National Corporation, et al. (the “Product Liability Matter”), filed in the Circuit Court of the City of St. Louis, Missouri (the “Circuit Court”), (2) September 5, 2024, a jury awarded compensatory damages of $12.0 million an…

Results of Operations and Financial Condition. On January 29, 2025, Wabash National Corporation (the “Company”) issued a press release announcing its financial results for the year and quarter ended December 31, 2024. A copy of the Company’s press release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. The press release and a teleconference visual presentation are also available on the Company’s Investor Relations website at ir.wabashnational.com.

Senior Vice President, Chief Commercial Officer — Kevin J. Page: Mr. Page is transitioning to a consulting and transition role as Senior Advisor.

Results of Operations and Financial Condition. On October 24, 2024, Wabash National Corporation (the “Company”) issued a press release announcing its financial results for the quarter ended September 30, 2024. A copy of the Company’s press release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. The press release and a teleconference visual presentation are also available on the Company's Investor Relations website at ir.wabashnational.com.

Other Events. As previously disclosed in Wabash National Corporation’s (the “Company”) filings with the Securities and Exchange Commission, the Company is and has been, and may in the future be, subject to product liability claims and litigation incidental to the Company’s normal operating activities. The Company has routinely defended lawsuits of this nature and considers this litigation to be in the ordinary course of business. On September 5, 2024, a jury awarded compensatory damages of $1…