Originally Posted by
Catboatsailor
I had this issue once before. I listed round trip to LHR and then after arriving I booked MAN-JFK and cancelled the LHR-JFK. If I were to guess I think the brits want to make sure you have a round trip planned. They don't like squatters.
One-way international tickets also carry a risk for the airline: if the passenger were denied entry at immigration for some reason, the airline is responsible for taking them back to their point of origin, whether or not said passenger can pay.
