American Airlines and British Airways have round-trip flights from Dallas (DFW) to London, United Kingdom (LGW/LHR) for $566-$589 NONSTOP, or with a connection. Flights October to February. Departures on Monday, Tuesday, Wednesday, and Sunday. 7-day minimum stay required.
COVID restrictions are currently in place, but this may be worthwhile for the dates this fall into 2022 depending on how things go with COVID moving forward.