Delta and Virgin Atlantic have a Christmas season sale from New York and Newark to London at $608 to $615 round trip. There are some straight nonstop flights with Virgin Atlantic between JFK and London LHR and there are some convoluted itineraries with Delta flights via Detroit and change of airports between Washington DCA and Washington Dulles IAD for some of these low fare tickets. Some itineraries have long overnight layovers in Boston or Philadelphia on return segments. Regardless of the routing, low $600s for New York to London at Christmas season is a limited time opportunity discount ticket.
Delta Airlines Newark EWR – Detroit DTW – London LHR – Detroit DTW – Newark EWR
$614.96 round trip Wed Dec 21 – Thu Dec 29 (Virgin Atlantic DTW – London LHR)
Delta Airlines Newark EWR – London LHR (Virgin Atlantic) – Detroit DTW (VS) – Newark EWR (DL)
Virgin Atlantic New York JFK – London LHR – Philadelphia PHL – New York JFK
This is one of the long layover itineraries with an overnight in Philadelphia on return. You can just grab your bags and catch a train to New York if you don’t want an overnight stay in Philadelphia waiting for the last flight. I also saw long layovers in Boston on return. Might not be bad if you have family or friends to visit in one of these cities.
There are flights from New York LGA too. Itineraries I saw required a switch of airports from DCA to IAD for the flight to London.