Delta Air Lines has relocated some of its key services to London Heathrow's Terminal 3, where it joins its transatlantic partner Virgin Atlantic.
Delta routes including those to New York JFK, Boston (BOS) and its new Seattle (SEA) service commenced operation from London Heathrow Terminal 3 on 2 April.
Delta flights between LHR and Atlanta (ATL), Detroit (DTW) and Minneapolis (MSP) continue to operate out of LHR Terminal 4.
The move is designed to "enhance convenience and a seamless customer experience".
Both Delta and Virgin Atlantic now operate their LHR to New York JFK services from Terminal 3, making it easier for passengers to manage any last minute flight changes.