Linnet's are a slim bird with a long tail. The upper parts are brown, the throat is sullied white and the bill is grey. The summer male has a grey nape, red head-patch and red breast. Females and young birds lack the red and have white underparts, the breast streaked buff.

The linnet derives its common name, from its fondness for hemp seeds and flax seeds—flax being the plant from which linen is made.

Open land with thick bushes is favoured for breeding, including heathland and garden. It builds its nest in a bush, laying four to seven eggs. This species can form large flocks outside the breeding season, sometimes mixed with other finches.