Heathrow and Edinburgh Airports welcomed 5.9 million and 826,000 passengers last month respectively - their busiest ever May - according to new figures published by operator BAA.
Both airports have also recorded their busiest ever spring period (March-May), with the six BAA-operated sites handling a total of 9.3 million passengers during May alone.
Meanwhile, Heathrow Airport saw the moving annual total number of passengers exceed the 68 million mark for the first time - boosted by the late Easter and the Royal Wedding.
Colin Matthews, chief executive of BAA, said: "Demand is particularly strong on the long-haul routes that connect UK businesses to fast-growing economies around the world."
Image: Heathrow Airport - Oleg V. Ivanov/shutterstock.com