Metsä Board Corporation Stock Exchange Managers' transactions 2 May 2025 at 16:00 p.m. EEST The Annual General Meeting of Metsä Board Corporation held on 20 March 2025 decided that approximately one half of the Board's annual remuneration is paid in the Company's B-series shares. Pursuant to such decision, the following shares have been acquired for and on behalf of the Board member Mikko Mäkimattila: Metsä Board Corporation - Managers' transactions - Mäkimattila ____________________________________________ Person subject to the notification requirement Name: Mäkimattila, Mikko Position: Member of the Board/Deputy member Issuer: Metsä Board Corporation LEI: 743700KKB8Q035K38488 Notification type: INITIAL NOTIFICATION Reference number: 743700KKB8Q035K38488_20250502104424_91 ____________________________________________ Transaction date: 2025-04-30 Venue: XHEL Instrument type: SHARE ISIN: FI0009000665 Nature of the transaction: RECEIPT OF A SHARE-BASED INCENTIVE Transaction details (1): Volume: 10259 Unit price: 0.00 EUR Aggregated transactions (1): Volume: 10259 Volume weighted average price: 0.00 EUR METSÄ BOARD CORPORATION Further information: Katri Sundström, VP, Investor Relations, tel. +358 10 462 0101 Eeva Impiö-Loimaala, General Counsel, tel. +358 44 040 3877 Metsä Board metsagroup.com/metsaboard (http://www.metsagroup.com/metsaboard/) Metsä Board is a producer of lightweight and high-quality folding boxboards, food service boards and white kraftliners. The fresh wood fibres we use in our products are a renewable and recyclable resource, that can be traced back to Northern European forests. We aim to have completely fossil-free mills and raw materials by 2030. We promote a culture of diversity, equality and inclusion. Metsä Board is listed on the Nasdaq Helsinki. In 2024 our sales totalled EUR 1.9 billion, and we have around 2,300 employees. Metsä Board is part of Metsä Group, whose parent company Metsäliitto Cooperative is owned by over 90,000 Finnish forest owners. Follow Metsä Board: LinkedIn (https://www.linkedin.com/company/metsa -board/) Instagram (https://www.instagram.com/metsaboard/?hl=en) YouTube (https://www.youtube.com/playlist?list=PLF6CD152EF0DA1E61)