Sadly this species arrives in Britian on vary rare occasions however it does have a widespread global distribution. It is a highly migratory species and occurs in Africa, southern Asia, Australia and southern European countries.

Many of the recent records in the UK are as a result of being imported in packs of mange-tout peas from supermarkets.

13-10-11 - Two Long-tailed Blues at St. Agnes, Isles of Scilly - at same location as that reported on 12-10-2011.
12-10-11 - Long-tailed Blue photographed egg-laying on gorse at St. Agnes, Isles of Scilly.
11-10-11 - Long-tailed Blue (female) seen by Peter Kitchener nectaring on bramble near Lowestoft, Suffolk (TM549955).
28-09-11 - Long-tailed Blue seen at Ladymead, Easton on Isle of Portland, Dorset.

05-09-09 - Long-tailed Blue on sweet pea at Felixtowe.

11-05-08 - Long-tailed Blue discovered by Faith & Christian Wilson in domestic compost bin at Glenealy, Wicklow (Probably imported from Kenya with mange-yout peas).

14-10-07 - Long-tailed Blue reported to me by Andy Gibson inside a house at Highcliffe Dorset (grid ref SZ 208 945). Sadly it was not photographed.
18-09-07 - Long-tailed Blue seen in Coggeshall Essex by Brian Corben. This is thought to be a genuine immigrant.
00-00-07 - 2x Long-tailed Blue larvae found in a pack of peas purchased from a CO-OP in Suffolk. These pupated and emerged as adult butterflies which the finder (Phil Evans) killed rather than releasing into the wild. Country of origin unknown.

09-10-06 - Long-tailed Blue at the end of Peninnis track, St. Mary's, Isles of Scilly.
28-08-06 - Long-tailed Blue seen in Ayrmer Cove near Bigbury, Devon on NT footpath (Grid Ref: SX 643 455)by Peter, Helen & Christopher Phillips.
25-08-06 - Long-tailed Blue (female) seen at Dawlish Warren, Devon (Grid Ref: SX 982 788) by Ivan Lakin & Kevin Rylands.
18-07-06 - Long-tailed Blue seen by Keith Knights at Bradwell, near Gt Yarmouth (in open ended poly tunnel at an aquatic plant nursery).

??-??-06 - Long-tailed Blue seen near Lowestoft. Further details unavailable.

??-08-90 - A small colony of the long-tailed blue butterfly was found on railway land at Gillespie Park Nature Reserve in Islington (Bevan, 1991). The females were found to be ovipositing onto the flowers of bladder senna (Colutea arborescens). Some of the resulting larvae were successfully bred in captivity. The colony failed to survive the following winter.

09?-05-88 - 2 Long-tailed Blue found inside a laboratory at Newforge Lane, Belfast, Co. Antrim, Northern Ireland (Probably imported with mange-yout peas).