The Himalayan Swiftlet is brown-gray overall with a pale gray rump and a squared-off tail. It belongs to a diverse and confusing group of swifts in the genus Aerodramaus. It is the easternmost ranging species in the genus and the only member throughout much of its range. Smaller than most other swifts in range except for House Swift, which is black overall with a sharp white rump and throat. Tends to travel in small to medium-sized flocks, often swooping low over bodies of water.