Mr. Bob Cross reports

STANDARD LITHIUM ANNOUNCES CHANGE TO BOARD OF DIRECTORS

Karen Narwold will resign from Standard Lithium Ltd.'s board of directors, effective Sept. 15, 2026, following her acceptance of a new executive position and the increased time commitments associated with her new role.

"We thank Karen for her valuable contributions and commitment to Standard Lithium during her tenure on our board," said Bob Cross, independent chairman of Standard Lithium. "We congratulate her and wish her continued success in this next chapter of her career."

Following Ms. Narwold's resignation, the board will consist of eight directors. The company has initiated a search process for a new independent director that will complement the board's existing experience, and expertise and support Standard Lithium's continued growth and strategic objectives. The company intends to announce an appointment following the conclusion of this process.

About Standard Lithium Ltd.

Standard Lithium is a leading near-commercial lithium development company focused on the sustainable development of a portfolio of large, high-grade lithium-brine properties in the United States. The company prioritizes projects characterized by high-grade resources, robust infrastructure, skilled labour and streamlined permitting. Standard Lithium aims to achieve sustainable, commercial-scale lithium production via the application of a scalable and fully integrated direct lithium extraction and purification process. The company's flagship projects are in the Smackover formation, an attractive lithium brine asset, focused in Arkansas and Texas. In partnership with global energy leader Equinor, Standard Lithium is advancing the South West Arkansas project, a greenfield project located in southern Arkansas, and actively advancing a promising lithium brine resource position in East Texas, including the highest known lithium brine grade project in North America, the Franklin project.

Standard Lithium trades on both the TSX Venture Exchange and the NYSE American under the symbol SLI.

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