The Victoria Underground line, with its southern terminal in Brixton, is to extend the operation of its most frequent service – a train each 100 seconds – for weekday morning and evening rush hours.
The high-frequency service currently operates from 8.15 to 9.45am and 5 to 6.30pm.
The new service will run from 7.15 to 10.15 am and 4.15 to 7.15pm.
Victoria line trains will continue to arrive every 135 seconds outside peak times.
Transport for London (TfL) said the boost to peak capacity would benefit hundreds of thousands of travellers every day and reduce crowding and congestion
The Victoria line is already one of the most frequent metro services in Europe. The new timetable will increase capacity by 5%, benefitting 275,000 customers each weekday.
The line is used by 250 million passengers each year and, running between Brixton and Walthamstow, serves Oxford Circus, Kings Cross St Pancras and Victoria, is among the busiest stations on the Underground network.
Brian Woodhead, London Underground director of customer service, said the new timetable would make stations and trains less crowded and journeys quicker and more comfortable.
Increased services at peak times on the Northern and Jubilee lines were introduced last year.
Victoria line Night Tube services on Fridays and Saturdays are unaffected.