Common Swift

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Common Swift in the UK

A summer visitor, usually just called Swift, that breeds across most of Britain and Ireland and is scarcer in the far north and west of Scotland. About 59,000 pairs nest in the UK. Numbers fell by 70% between 1995 and 2024, and it was added to the Red List in 2021. The causes are not fully understood. Loss of nest holes as old roofs are repaired or replaced is one, and lower survival of young birds appears to drive the trend. Birds arrive from late April and most have left by mid August. They winter in Africa south of the Sahara.

Where and when to see a Common Swift

Look up over towns and villages with older buildings, churches and terraces from May to early August. Screaming parties race round the rooftops at dusk in June and July, which is the best way to find a colony. In cold or wet weather, especially in May, hundreds gather low over lakes, reservoirs and gravel pits to feed. Fine evenings bring them high over any open country. A few late birds pass along the coast into September, and any swift from October on should be checked for a rarer species.

Habitat, diet and field notes

Habitat: Skies above towns, villages (summer).
Diet: Aerial plankton.
Field note: Sleeps and mates on the wing.

How to identify a Common Swift

Larger than a Swallow, with long, narrow, stiff wings swept back in a crescent. It is sooty brown all over and looks black against the sky, with a small pale throat patch that is hard to see. The tail is short and forked. It never perches on wires or the ground. Flight is fast, with bursts of flickering beats on stiff wings between long glides. Juveniles in late summer have a whiter throat and pale scaling on the forehead.

Call and song

A shrill, piercing scream, 'sreeee', given in flight and often by groups chasing together. It carries a long way on summer evenings. Birds in the nest answer with the same call. Heard something you cannot place? Bird Hear identifies UK birds from a 10 second recording, free in your browser.

Confusion species

• Barn Swallow: Swallow has cream underparts, a red throat and long tail streamers, and often perches on wires.
• Western House Martin: House Martin is smaller with pure white underparts and a square white rump, and has a fluttering flight.
• Pallid Swift: Pallid Swift is a rare late autumn vagrant that is paler and browner with a larger white throat, a dark eye mask and blunter wingtips.

Month by month

A summer visitor, typically in the UK from May to August. Numbers peak in June. See the June birding guide for what else is about. More on the season in Bird migration in Britain.

Taller bars mean more birds about. Grey means it is usually absent.

Conservation status and Birdedex points

In the Birdedex the Common Swift is a Common tier bird, worth +1 point when you log one. It is Red-listed in Birds of Conservation Concern 5, the highest level of concern in the UK.

Recent UK sightings

Similar birds

• Little SwiftLegendary · Cliffs (very rare vagrant)
• Pacific SwiftLegendary · Open sky (extreme vagrant)
• Pallid SwiftRare · Coast
• Plain SwiftLegendary · Coast (very rare)
• White-rumped SwiftLegendary · Cliffs (very rare)
• Western House MartinCommon · Villages

Tell it apart

Side-by-side ID guides: Swift vs Swallow vs House Martin.

Common Swift: quick answers

When do Swifts arrive in and leave the UK?

The first arrive in the last days of April and the bulk in the first half of May. They are among the first summer migrants to go: breeding birds leave from mid July, and most streets are silent by the middle of August.

Do Swifts really sleep on the wing?

Yes. Outside the nest a Swift feeds, drinks, mates and sleeps in the air. Tracking studies have shown that some birds stay airborne for the whole ten months between breeding seasons. Young birds may not land for two or three years.

How can I help Swifts?

Keep existing nest holes open when roofs or soffits are repaired, and avoid work between May and August. Fit a swift nestbox under the eaves or a swift brick in new walls, at least five metres up with a clear flight path. Playing swift calls nearby helps birds find new boxes.

Kit that helps

Best nest boxes for UK birds. Affiliate links, our own picks, no extra cost to you.