Delta Air Lines and Virgin Atlantic Airways are expanding their trans-Atlantic partnership with six new daily services. Their summer schedule offers up to 39 return trans-Atlantic flights per day between the United Kingdom and 15 destinations across North America.

“The Delta and Virgin Atlantic partnership continues to offer increased customer choice on the trans-Atlantic routes to London Heathrow — in particular from New York,” said Perry Cantarutti, senior vice president, Europe, Middle East and Africa, Delta Air Lines. “The strength of Delta’s network in the United States and Virgin Atlantic’s strong presence at London Heathrow delivers a very compelling proposition that allows customers in the U.K. to easily connect to more than 200 destinations in the United States.”

The joint schedule includes 10 daily flights from the New York area and London (LHR), with eight daily departures from New York (JFK) and two departures from Newark (EWR).

Between Los Angeles (LAX) and London, Virgin Atlantic is launching a second daily service. The route boost complements the airline’s significant investment on the ground with the debut of its first-ever Virgin Atlantic Clubhouse in Los Angeles this month. Combined with the Delta service launched last year, the partnership offers three daily flights from Los Angeles to London, carrying close to 400,000 annual passengers on the route.

Also recently launched are Virgin Atlantic’s second daily service between Atlanta (ATL) and London and second service between San Francisco (SFO) and London, operating five times per week over the summer.