As an example, I found seats departing DFW on Tuesday, November 19, returning from LHR on Tuesday, November 26, 2019.
Tickets at this price point can be found from October through early December, then again from mid January through the end of booking schedule.
Departures from DFW are valid Sunday through Wednesday, returns from LHR are available Tuesday through Friday. A Saturday night stay is required.
This international Basic Economy fare only includes one small personal item and a full-size carry-on bag. Checked bag fees start at $60 each way.
Seats will be assigned at random upon check-in for this price. You may pay a fee (for each flight leg) to choose specific seats.
For an additional $160 roundtrip, you can purchase a standard Economy fare, which includes standard advanced seat selection, one piece of checked luggage, and allows ticket changes/upgrades for a fee.
Related: How to Fly United Airlines
See our fare details for booking info.
Need a room in Londontown? Here's what's available for the above dates on Hotelwatchdog.