I came across this $551 round trip ticket with American Airlines for New York JFK – London LHR that prices lower than $625 shown on Google Flights with British Airways nonstop outbound and Aer Lingus return via a 24 hour layover in Dublin. Not a deal for everyone, but certainly a deal for the right flyer considering SkyTeam and Star Alliance carriers are all priced over $700 round trip to London from New York and this ticket gives you a free full day in Dublin on top of London.
This is a challenging fare to locate. I don’t see it price on ITA Airfare Matrix or Google Flights.
Only guidance I can provide is Google Flights fares showing up at $625 and $639 for Nov-Dec re-price at $551 and $565 an American Airlines when British Airways nonstop is outbound and Aer Lingus inbound with 24 hour transit layover in Dublin and some other combinations like AA to Spain and Aer Lingus.
American Airlines New York JFK – London LHR British Airways (nonstop) – Dublin Aer Lingus (24 hour layover 4:10pm-4:10pm) – New York JFK
$550.66 round trip Nov 14 – Nov 21 (Dublin) – Nov 22 JFK
American Airlines New York JFK – Barcelona BCN AA (nonstop) – London LGW – Dublin Aer Lingus (24 hour layover 4:10pm-4:10pm) – New York JFK
$564.16 round trip Fri Dec 2 – Wed Dec 7 (Dublin 24 hours) – Thu Dec 8 DUB-JFK
Google Flights Fare Calendar Nov-Dec
$625 re-prices at $551 Nov 4, 14
$639 re-prices at $564 Nov 23, 28, Dec 2
There might be more dates. I tried a couple of dates in February and March at $625 and $639 and they priced on AA at $625/$639 price.
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