The over-budget project was meant to open in December 2018 but will now begin running on 24 May.
The delayed and over-budget Crossrail project will finally open this month, Transport for London (TfL) has said.
The Abbey Wood to Paddington section will open to passengers on 24 May, although initially trains will not run on Sundays or call at Bond Street.
Known as the Elizabeth line, it was due to open in December 2018 but the project has faced numerous setbacks.
The Elizabeth line will link Reading and Essex via central London.
Once the route is open, services will run every five minutes between 06:30 BST and 23:00, although a full timetable will not be in place until May 2023.
The opening date is also subject to final safety approvals being granted.
TfL said there would be a special Sunday service for the Platinum Jubilee weekend.
Previously, transport bosses would only commit to an opening date during the first half of 2022.
The project had an original budget of £14.8bn, but the government pledged an extra £4bn to help get it open.
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- 16 November 2021