The eastern woodrat, though large, is mouse-like in general appearance.
Females have six nipples.
In their second year the grayish young attain the rich buff pelage of adults. The eastern woodrat is most frequently associated with trees, either along stream courses in the western part of the state, or in deciduous forests in the east. In both areas it prefers rock outcrops as den sites. There is a lull in breeding in mid-summer. At birth the eyes of the young eastern woodrat are closed and the body naked or only slightly haired with gray pigmentation on the back of the head and sides.