Kestrels at Heathrow is open every day except Saturday. A relaxing place with swimming pool etc
Abfabs at Heathrow on Monday, Wednesday, Friday and Saturday evenings for great parties.
While it’s not exactly in London but Penthouse Playrooms in Dunstable is a very good club.
it’s just outside the M25 so not too far from London, the club has great reviews on Fabs and is worth checking out if you are in the London area.