Passengers will be able to travel from Abbey Wood to Paddington starting on May 24, though trains will not run on Sundays or stop at Bond Street at first.
Services in central London will run every five minutes between 6.30 a.m. and 11 p.m. once the route is open, but a full timetable will not be in place until May 2023.
Until next year, passengers who want to travel the entire length of the line will have to change at Paddington or Liverpool Street, depending on their destination.
When the line reaches Whitechapel, it splits into two different directions. One of these will travel southeast, stopping at Abbey Wood.