How long should it take to go through customs when arriving at Heathrow?
We generally arrive at Gatwick, but have found both Heathrow and Gatwick to be similar. It depends on how many other flights arrive at about the same time as yours. Sometimes we have gotten through in less than 5 min. Other times it has taken almost an hour.
There is no way of telling how long it will take to get through passport control at any airport. All it takes is a family of deportees ahead of you in the queue and everything grinds to a halt. Sadly at LHR this happens quite a lot. Even if you arrive at a time when there are not many arrivals you can get stuck in a queue because someone has handed over a bogus passport and further measures need to be taken. It happens everywhere. I’ve been stuck in a queue at O’Hare for over 90 minutes. All of that having been said I have never known Heathrow to take more than 90 minutes at the outside for anyone holding a US passport.