The male is brightly coloured with a blue-grey cap and rust-red underparts. The female is much duller in colouring but both sexes have two contrasting white wings-bars and white sides to the tail. The male bird has a strong voice and sings from exposed perches to attract a mate.

The chaffinch is about 14.5 cm long, with a wingspan of 24.5–28.5 cm and a weight of 18–29 g.

The powerful song is very well known, and its fink or vink sounding call gives the finch family its English name. Males typically sing two or three different song types, and there are regional dialects too.

Nests are built entirely by the female and are usually located in the fork of a bush or a tree several metres above the ground