As its name implies, it is the largest member of the genus Artamus, averaging 20 centimetres (7.87 in) in length and 61 grams (2.2 oz) in mass.

[2] Like its smaller relatives, the great woodswallow is a fast-flying aerial insectivore feeding chiefly on large flying insects.

It is generally regarded as the smallest bird in the world that habitually soars on updrafts over long distances, but it will also use its feet to manipulate its insect prey.

Great woodswallows are highly social, flying in flocks of up to twenty birds, and nomadic over their montane forest habitat.

They usually breed between August and December, and the nest is like other woodswallows: a flat platform of grass or twigs in a tree hole or stump, though higher above the ground than other species in the genus.