Sienna Corporate Update

VANCOUVER, BC, March 25, 2026 – Sienna Resources Inc. (TSX.V: SIEN) (FSE: A418KR), (the “Company” or “Sienna”) wishes to announce that it has granted a total of 1.475 million stock options to its directors and consultants at an exercise price of twelve cents per share for a period of 12 months. The Company also granted a total of 3.05 million restricted share units (RSUs) to its directors, officers and consultants. The RSUs vest in one year from the date of grant. The options and the RSUs have been granted and vest in accordance with the Company’s omnibus equity incentive plan and the policies of the TSX Venture Exchange therefore aligning management with the shareholders of the Company.

Contact Information Tel: 604-646-6900 www.siennaresourcesinc.com

“Jason Gigliotti” President Sienna Resources Inc.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.