The Eastern Cottontail, Sylvilagus floridanus, is a New World cottontail rabbit, a member of the family Leporidae. This is probably the most common rabbit in North America.

These are chunky red-brown or grey-brown rabbits with large hind feet, long ears and a short fluffy white tail. Their underparts are white. There is a rusty patch on the nape.

They are found in meadows and shrubby areas in the eastern and southwestern United States, southern Canada, eastern Mexico and Central America. Their range expanded north as forests were cleared by settlers. Originally, the Eastern Cottontail was not found in New England, but they have been introduced there and now compete for habitat there with the native New England Cottontail .

They eat green vegetation such as grasses and clover in summer and bark, buds and twigs in winter. These animals are active at night; they do not hibernate in winter. Predators include hawks, owls, mustelids and lynx. People also hunt them for food in many parts of their range; their fur is also used for clothing.

Males will mate with more than one female. Female rabbits have 2 to 4 large litters of up to 7 young in a year; they build a nest on the ground lined with grass and fur. Young females are often able to breed at 3 months.