I made a huge mistake on my connecting flight to Amsterdam via London Heathrow. If I did the math right, I only have an hour and a half to make my connecting flight to Amsterdam at London Heathrow's Terminal 5. I arrive and depart in the same terminal, but I might be cutting it close. I've been searching the internet to find out if I need to go through customs first before connecting, but I thought I'd only have to go through customs on my final destination, which is the Netherlands. The British Airways website and the London Heathrow websites do not provide enough information on this subject. I'll keep searching on the old internet to see what I can come up with, because well, I just have that kind of time.