The largest UK tit - green and yellow with a striking glossy black head with white cheeks and a distinctive two-syllable song. It is a woodland bird which has readily adapted to man-made habitats to become a familiar garden visitor. It can be quite aggressive at a birdtable, fighting off smaller tits. In winter it joins with blue tits and others to form roaming flocks which scour gardens and countryside for food. Great tits feed on insects, such as caterpillars spiders, seeds and berries. In the garden they will feed from hanging feeders containing nuts and seeds, such as sunflower hearts, or on kitchen scraps from bird tables. They will nest in a hole in a tree or wall, or among the twigs of old nests. The nest is a cup made from moss, grass and down, and lined with hair, plant down and feathers. Garden nest boxes are frequently used.

The Great Tit's eggs are the largest of the British tits at 18mm by 14mm; they are smooth and glossy, and white with purplish-red spots. The female incubates the eggs by herself. After the young hatch, they are fed by both parents.