The changes are due to engineering work and will affect trains on Saturday and Sunday (June 28 and June 29).
We have outlined and simplified the details so you can plan your journey this weekend.
Sunday (June 29):
Engineering work is taking place between Norwood Junction and Epsom Downs via West Croydon, closing all lines.
All day on Sunday, trains between London Victoria and Epsom Downs will be diverted to run between London Victoria and East Croydon.
Replacement bus services will run between East Croydon and Epsom Downs via West Croydon, calling at all stations.
Saturday and Sunday (June 28 and June 29):
Engineering work is taking place between Balham and Crystal Palace or Norwood Junction, closing some lines overnight.
On Saturday, from 11.30pm until the end of service, trains between Balham, Streatham Hill, Crystal Palace, London Bridge, and Norwood Junction will run to an amended timetable.
Replacement buses will replace trains between Balham, Streatham Hill and London Bridge via Crystal Palace and Sydenham, and between Balham and Norwood Junction via Crystal Palace.
On Sunday, until 9am on Sunday morning, trains between Balham, Streatham Hill, Crystal Palace, London Bridge, and Norwood Junction will run to an amended timetable.
Buses will replace trains between Balham and London Bridge via Crystal Palace and Sydenham.
Trains will run to an amended timetable with extended journey times between Balham and Mitcham Eastfields.
Trains to London Victoria will not call at Battersea Park.
Passengers travelling to London Victoria should travel via Clapham Junction.
Passengers for Battersea Park should travel to London Victoria, then catch the next train back to Battersea Park.
Trains between London Bridge and Caterham will be diverted between London Bridge and East Croydon and will run to an amended timetable with extended journey times.
