Western yellow wagtails breed in much of temperate Europe and Asia. They are residents in the milder parts of their range, such as western Europe, but northern and eastern populations migrate to Africa.
The yellow wagtail is a slender 15–16 centimeter long bird, with the characteristic long, constantly wagging tail of its genus. It has the shortest tails of the European wagtails. The breeding adult male is basically olive-colored above and yellow below. In other plumages, the yellow may be diluted by white. The heads of breeding males come in a variety of colors and patterns depending on its subspecies.