The carrier will recommence its Seattle service on 7 October, flying three times a week.
Four flights a week to Detroit will restart on 11 October.
In addition, Heathrow-JFK flights will double to twice a day from 6 October. The carrier is also flying daily to its main hub at Atlanta from London.
Delta is ramping up services across the pond to nearly 30 weekly flights following the reopening of the gateway between the US and UK to fully vaccinated US citizens on 2 August. However, UK visitors are still barred from the US without good reason.
“This long-awaited reopening marks a major milestone since the borders closed to most travellers more than a year ago,” said Joe Esposito, Delta’s senior vice president, network planning.
To travel to London, passengers will need to provide both proof of vaccination and a negative test (PCR, LAMP or antigen) taken within three days of departure. They must take a PCR test on or before two days after arrival. To re-enter the US, customers must provide proof of a negative test within three days of departure