Originally Posted by
chuckd
One constant is do not fly out of LHR. Taxes and fees generally kill any savings.
While award tickets are frequently messy going into LHR, paid tickets, while not as cheap as going into Dublin, paid tickets are often really not that bad. My Skyteam captive self can usually find flights cheaper into there than a lot of European cities unless someone's having a fare sale ala the fare war with Norwegian this year or Turkish's cheap routings through Istanbul in 2013.
My theory is that, while BA has a ton of gates at LHR, there's enough genuine competition for those flights into London that that airlines end up taking a slightly lower profit margin on that route per flight than some other common European destinations with fewer transatlantic options and hope to make up for it in terms of flight volume.