English sole are flatfish that inhabit the Pacific Ocean, from the Aleutian Islands down to Baja California, Mexico. In Canadian waters, the densest populations occur off the coast of British Columbia. They are migratory but usually do not undertake long migrations. They can live at depths of more than 500 metres, but are usually found at depths of less than 150 metres.

English sole are diamond-shaped and have flat, compressed, brown to olive-brown coloured bodies, sometimes mottled with white. They are righteye flounders with their second eye set high and visible from the blind side. Their blind side ranges from white to a muted yellow with a brownish tinge. They have small, asymmetrical mouths and pointed snouts, and can grow to more than 50 centimetres in length and weigh more than a kilogram. Females usually are much larger than males and constitute the majority of the commercial catch.