Hey neighbor: American Airlines and British Airways move in together at JFK Terminal 8

American Airlines and British Airways are set to become "roommates" as their CEOs called it, moving into the same terminal at New York’s John F. Kennedy International Airport for the first time, beginning Thursday.

The two carriers are among the closest partners in the transatlantic market, with passengers often connecting between them on multi-leg international trips. Taken together, AA and BA operate nearly hourly service between JFK and London throughout much of every day.

Executives and elected officials say the move, which is part of a larger overhaul at JFK, will make things easier for customers of both airlines and many of their partners as well.

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What can travelers expect?

American Airlines and British Airways jointly invested $400 million to expand JFK Terminal 8 and make this co-location possible. According to American CEO Robert Isom, the changes are all about improving the customer experience.

Both airlines want to "ensure that we can offer a seamless service for customers who want to transit through JFK to anywhere in the world," he said during a ribbon-cutting event for the redeveloped terminal on Tuesday. Bringing the airlines together under one roof, he said, will result in "reduced connection times, faster security screenings and enhanced, personalized, seamless travel experience overall."

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British Airways has been using Terminal 7 at JFK since 1970. BA and AA have been partners through the oneworld alliance since 1999 and joint venture partners since 2010. These close ties have given passengers more connecting itinerary options at their hubs, but separate terminals at JFK have also meant that their customers have always needed to change buildings and go through security again to make connections between the two.

That particular headache will soon be alleviated.

"It's all about treating our customers as one customer and making the connection, check-in experience and lounge experience as consistent and seamless as possible, so this is the start of a new chapter of deeper integration with American Airlines," British Airways CEO Sean Doyle said at Terminal 8 on Tuesday.

What other changes are coming to JFK?

Eventually, Terminal 7 will be torn down and a new Terminal 6 will be built in its place. Terminal 1 is also being redeveloped, and airlines will continue shuffling during construction.

Spanish airline Iberia will join AA and BA in Terminal 8 on Thursday as well, and Japan Airlines will relocate there next year according to Tuesday's press briefings.

JetBlue, another American Airlines partner at JFK, does not plan to move from its Terminal 5 home, but Isom said there is efficient bus service for customers transferring between the two airlines.

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Will premium passengers get any new perks?

As part of the terminal renovation, two new lounges are opening at Terminal 8, and a third is being rebranded to help the airlines further integrate their ground experiences.

The top-tier Chelsea Lounge offers a fire pit, champagne bar and a la carte dining, and is available to certain Flagship travelers and ConciergeKey members on some American Airlines itineraries, and British Airways customers with Concorde Room access.

The larger Soho Lounge features floor to ceiling windows and a cocktail bar, and like Chelsea, offers guests the opportunity for a private shower before or after their flight. American Airlines Executive Platinum and Platinum Pro passengers on certain Flagship itineraries can enter, as can British Airways customers with First Lounge access.

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The Greenwich Lounge, formerly the Flagship First Lounge for American passengers, has a terrace bar and varied seating options, and is available to American Airlines customers traveling in Flagship Business, or AAdvantage Platinum members on qualifying itineraries. British Airways customers with Club Lounge access will be eligible to visit Greenwich.

This article originally appeared on USA TODAY: American Airlines and British Airways buddy up at JFK Terminal 8