0001408075 2026-09-28 2026-09-28 false 0001408075 8-K 2026-09-28 Graphic Packaging Holding Company DE 001-33988 26-0405422 1500 Riveredge Parkway Atlanta GA 30328 770 240-7931 false false false false Common Stock, $0.01 par value per share GPK NYSE false