It breeds in tropical southern Asia and the islands of the south Pacific.

The Pacific swallow was formally described and illustrated in 1789 by the Swedish naturalist Anders Sparrman based on a specimen collected on the Indonesian island of Java.

[5] Six subspecies are recognised:[5] This species is a small swallow at 13 cm (5.1 in) in length.

It has a blue-black back and crown with browner wings and tail, a red face and throat, and dusky underparts.

[2][6] The Pacific swallow builds a neat cup-shaped nest, constructed with mud pellets collected in the beak, under a cliff ledge or on man-made structures such as a building, bridge or tunnel.