Exhibit 99.1 News Release International Paper Reports First Quarter 2024 Results MEMPHIS, Tenn. – April 25, 2024 – International Paper (NYSE: IP) today reported first quarter 2024 financial results. FIRST QUARTER 2024 HIGHLIGHTS • First quarter net earnings of $56 million ($0.16 per diluted share) • First quarter adjusted operating earnings (non-GAAP) of $61 million ($0.17 per diluted share) • First quarter results negatively impacted by approximately $52 million (pre-tax) due to January freeze and Ixtac, M ...