Transport for London (TfL) has confirmed plans to roll out Night Tube services to the Metropolitan, Circle, District and Hammersmith & City Lines once a major upgrade programme is complete in 2023.
It also revealed it has spent over £2m in an effort to crack down on additional noise and disturbance from the Night Tube since services began in 2016.
Papers for a customer service and operational performance panel meeting this week said: "In the future, the Night Tube will be extended to parts of the Metropolitan, Circle, District, and Hammersmith & City Lines, once the £5.4bn modernisation programme is completed in 2023."
The work includes the introduction of a new signalling system, to help improve the Circle, District, Hammersmith & City and Metropolitan Lines, and allow trains to run closer together, resulting in a more frequent service and shorter waiting times.
The Night Tube began on the Central and Victoria Lines in August 2016 and then came to the Jubilee, Northern and Piccadilly Lines. Night services then started on part of the London Overground last month, and the mayor has said the DLR will be looked at when its contract next comes up in 2021.
In this week's report looking at the Night Tube one year on, TfL said £2.4m had been spent since 2016 to make improvements and cut down noise troubles. Up to mid-November 2017, it had received 372 complaints about Night Tube noise.
Of those, 222 have been resolved - deemed as such when a resident is satisfied the noise level has been reduced, or when there are no further actions engineers can take to deliver more improvements.
The economic impacts of the Night Tube have been greater than originally expected, boosting the capital's economy by £171m. London First and EY now predict the Night Tube will add £138m to the capital's economy annually for 30 years.
Key benefits TfL has noted include significant time savings for workers and passengers making leisure trips, generating revenue.
TfL said the Night Tube has cut late-night journey times by an average of 20 minutes, and in some cases up to an hour, generating around £10m in total revenue for the transport body.