The short, soft, smooth fur is not sharply bicolored, for the underparts are only slightly paler than the upper parts. The color varies from almost black through gray and brown to almost white. Western pocket gophers have a robust body, short legs, small eyes and ears, and long front claws. The slightly tapered, thinly haired tail is naked at the tip. Unlike in most other geomyids, the incisors of Thomomys usually lack frontal grooves.
Females have three to seven pairs of mammae, depending on the species.
Western pocket gophers inhabit many kinds of soil, from sea level to about 4,000 meters in elevation. They live in deserts, prairies, open forests, and meadows. These pocket gophers are primarily fossorial and spend most of their lives underground. Their burrow systems consist of deep permanent galleries and shallow feeding tunnels. The feeding tunnels radiate out from the central galleries and are about 50 mm in diameter and 130-460 mm deep.