The checklist of British and Irish Braconidae is revised, based in large part on the collections of the National Museums of Scotland, Edinburgh, and the Natural History Museum, London. Distribution records are provided at the country level together with extensive synonymy and bibliography. Of the 1,338 species regarded as valid, presumed native and certainly identified, 83 are here recorded for the first time from the British Isles. One new synonym is established (Dyscritus suffolciensis Morley, 1933 = Syntretus splendidus (Marshall, 1887) syn. nov.)