Angophora costata subsp. euryphylla is a tree that typically grows to a height of and forms a lignotuber. It has smooth pinkish to orange bark that weathers to grey. Young plants and coppice regrowth have sessile leaves with a stem-clasping base that are egg-shaped, long, wide and arranged in opposite pairs. Adult leaves are also arranged in opposite pairs, glossy green above and paler below, lance-shaped or curved, long and wide on a petiole long. The flower buds are arranged on the ends of branches on a branched peduncle long, each branch of the peduncle usually with three buds on pedicels long. Mature buds are globe-shaped, long and wide, the floral cup hairy with longitudinal ribs. The sepals are up to long. The petals are white with a green keel and long, wide. Flowering has been observed in November. The fruit is a cylindrical to barrel-shaped capsule long and wide on a pedicel long.
