Males sing a long and variable series of twitters and warbles that can be several seconds long. The notes and phrases are variable and repeated in a seemingly random order. Birds continue to learn song patterns throughout life.
The American Goldfinch’s most common call is its contact call, often given in flight. It sounds like the bird is quietly saying po-ta-to-chip with a very even cadence. Birds sometimes give harsh threat calls when in feeding flocks or at the nest. Males make a tee-yee courtship call upon landing near a female in spring or early summer, often followed by a burst of song. Females brooding nestlings make a rapid sequence of high notes when they hear their mate approaching with food. Birds at their nest make a loud, two-parted bay-bee call if they feel threatened.