The violet-green swallow closely resembles the tree swallow but is recognized by the large amount of white on the face and the conspicuous white patches at the sides of the rump. It is a western species, breeding from northern Alaska south throughout the West to the edge of the Great Plains.
Although common, it is still less abundant than tree swallows and tends to migrate individually or in small groups, rather than in immense flocks. It nests in natural cavities and bird boxes, and where it overlaps with tree swallows, is often found at higher elevations. The song is similar to that of tree swallows but is less clear and whistled and often includes a rapid series of chip notes.
The most common call is very similar to a tree swallow, but is even more twittering, much like the call of a swift.
