Originally Posted by boifromtroy
WHY WHY WHY?!?
You can book an ORD-LHR round trip and make a stopover in AMS on the return for the cost of your ORD-LHR ticket!
So it goes: ORD-LHR then LHR-AMS-(stopover)-ORD
All on one ticket.
You can only do this if your fare allows stopovers and not all fares do, in particular, the cheapies. Also, I believe UA flies a 767 on that route which some prefer to avoid.