How many hours do we have to check in before our flight at Gatwick or Heathrow?
You need to be in the check in queue 2 hours before departure. We recently spent a whole hour in the Heathrow check in queue due to the thicko morons in front of us! Then the security was total chaos (not enough security people and machines in action and being ultra pernickity!) so we had to rush straight through to the departure lounge and immediate check in and boarding!