The shoulders and underparts are pinkish. The head has a white crown with black marks above the eyes and into the nape. They have red eye rings and a very small black bill. The black and white tail is very long, over half the length of the bird and the longest tail of any British bird in proportion to its body. The legs are black-brown.

They feed mostly on insects and their larvae, and spiders, but also on berries. Increasingly, Long-tailed Tits are feeding from peanut feeders and suet cake in gardens.

The Long-tailed Tit's nest is an elastic ball of moss, spiders' webs, lichen, feathers, and hair that is built by both birds in a bush, hedge or tree; brambles and gorse are favourite places. The nest may take up to 3 weeks to build and be lined with more than 2000 feathers. Long-tailed Tits are resident and mostly sedentary throughout the UK.