Stations on a section of the Central Line will be re-zoned from 2 January in an attempt to raise passenger numbers.
Service hours on the Hainault loop were extended last month
Barkingside, Fairlop, Hainault, Grange Hill, Chigwell and Roding Valley, in east London, are being moved from zone five to zone four.
The stations, which form the Hainault loop, are being re-zoned to attract more passengers, Tube officials said.
By making the change, passengers travelling between the stations and central London will pay lower fares.
General manager for the Central Line, Jeff Ellis said: "Passenger numbers on this part of the line have traditionally been low compared to other parts of the Tube network."
He said their aim was "to increase passenger demand on this section of the Central Line".
Last month services to the Hainault loop were extended and the route began operating beyond 2000 GMT.