Air distance from Saint-Denis, Reunion (French) to London, UK is 5982.3 Miles (9627.6 Kilometers / 5195 Nautical Miles).
12 hrs, 25 mins is the flight duration between Saint-Denis and London. This is the In-The-Air flight time. You should also add the taxi time, airport wait times and possible delays due to bad weather, etc. for the total flight duration time.