Goldfinches migrate from the northern United States and parts of Canada to the southern parts of the U.S. during the late fall and early spring months. They are occasionally spotted as far south as Mexico.
The American Goldfinch breeds during the summer months in parts of Canada and in several northern states, including North and South Dakota, Montana, and Minnesota. If the food supply is adequate, many birds remain in the north instead of migrating. Goldfinches can often be found year-round in the Central and Midwestern United States as well as on the East Coast. They tend to breed later than most North American species, waiting until June or July, coinciding with the availability of the milkweed and thistle seeds they use in their nests.