Alliance Resource Partners LP

Delaware ​ ​ ​ 73-1564280 (State or other jurisdiction of incorporation or organization) ​ Commission File No.: 0-26823 ​ (IRS Employer Identification No.)

ITEM 1.01. ENTRY INTO A MATERIAL DEFINITIVE AGREEMENT. ​ On July 1, 2026, ARLP and its subsidiaries acquired certain assets located outside the United States and, in connection with such acquisition, we entered into the following related party agreement: ​ Master Supply, Distribution, and Services Agreement ​ On July 1, 2026, Matrix Design Africa (PTY) LTD ("Customer"), a wholly owned subsidiary of Alliance Resource Partners, L.P. ("ARLP"), entered into a related party agreement (as discussed below), consisting of a Master Supply, Distribution and Services Agreement (the "Master Supply Agreement") with Saminco Solutions LLC (the "Supplier"), pursuant to which the Customer has the right (but not the obligation) from time to time to (a) act as the Supplier's non-exclusive distributor for certain products in Africa and other territories outside the United States, (b) purchase products from the Supplier, (c) obtain services from the Supplier, including in respect of the repair and refurbishment of products, in each case subject to the terms and conditions of the Master Supply Agreement. Further, the Master Supply Agreement provides the Supplier with the right (but not the obligation) from time to time to purchase products from the Customer for incorporation into its own products for resale. ​ The purchase price for any product shall be set forth in the applicable purchase order and, unless otherwise specified in the applicable purchase order, the amount payable for any services shall be based on the Supplier's hourly labor rate then in effect and applicable to all customers of the Supplier. Prices charged and billed to the Customer for products and services shall be no less favorable to the Customer than those generally extended to other similarly situated customers of the Supplier ordering similar products or requesting similar services under similar circumstances, unless otherwise agreed in a purchase order. ​ The initial term of the Master Supply Agreement is five years, and the initial term shall automatically renew for successive periods of one year each unless a party gives notice of termination at least 30 days prior to the then expiring term. The Master Supply Agreement may also be terminated at any time by a party without cause upon the giving of at least 90 days prior notice. The Customer has the right to cancel any product or service purchase order under certain circumstances, including on account of the Supplier's non-performance. The Master Supply Agreement contains other terms and conditions customary for a transaction of the type contemplated by a master supply, distribution, and services agreement, including with respect to applicable warranty periods, warranty repair obligations, acceptance and rejection of products and services, limitation of liability, force majeure, and indemnification for certain matters arising out of the subject matter of the Master Supply Agreement. ​ The foregoing description of the Master Supply Agreement is a summary only and is qualified in its entirety by reference to the complete text of the agreement, which will be filed as an exhibit to the Partnership's periodic report for the period in which such agreement is required to be filed. ​ Related Party Transactions ​ The Supplier is a company affiliated with Joseph W. Craft III, who owns Alliance Resource Management GP, LLC, the managing general partner of ARLP (the "MGP"), beneficially owns approximately 14.6% of the common units, representing limited partner interests in ARLP, and is the President and Chief Executive Officer, and Chairman of the Board of Directors of MGP (the "Board"). The terms of the Master Supply Agreement were reviewed and approved by the conflicts committee of the Board (the "Conflicts Committee"), which is composed entirely of independent directors. The Conflicts Committee determined that the transactions with the Supplier were fair and reasonable to the Partnership and its unitholders. ​ ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS. ​ (d) Exhibits ​

Exhibit Number Description ​ 104 ​ Cover Page Interactive Data File (formatted as inline XBRL).