The appearance depends on the age of the plant; when young they form a basal rosette of oval to lanceolate leaves 4 to 10 cm long, and when they get older, forked stems grow from these, with leaves in opposite pairs. The flowers grow in clusters at the tops of the stems, 2.5 to 3 cm diameter, with a distinctive inflated calyx and five white petals, each petal deeply notched; flowering lasts from late spring to early autumn. The entire plant is densely hairy. Occasional plants with pink flowers are usually hybrids with red campion (Silene dioica).
White campion grows in most open habitats, particularly wasteland and fields, most commonly on neutral to alkaline soils. Flowering lasts from late spring to early autumn.