This butterfly is seasonally variable. The upperside of the summer form’s hindwings are all black, whereas the winter forms hindwings are reddish orange. The underside of both forms is striped with dark and light brown. There is a silvery comma mark in the middle of the hindwing in both forms. Its wingspan is 4.5–6.4 cm (1.8–2.5 in).
The eastern comma may be spotted in woods near rivers, ponds, marshes, swamps, and other water sources. Seldom visits flowers, but rather feeds on sap, rotting fruit, salts and minerals from puddling, and dung.