Engineering work is taking place between Reigate and Redhill, closing some lines.
Buses will replace trains between Reigate and Gatwick Airport.
All day on Saturday and Sunday, trains will be diverted between Purley and Horley and will not call at stations via Redhill.
Replacement buses will run between:
Direct trains between London Victoria and Reigate will not run.
Trains that usually run between Redhill and Tonbridge will only run between Edenbridge and Tonbridge.
Southern trains running between London Victoria and Brighton will call additionally at Purley and Horley, to provide connections with replacement bus services.
No trains will call at Coulsdon South, Merstham, Redhill or Earlswood.
Rail replacement buses will run between Purley and Horley, calling at Purley, Coulsdon South, Merstham, Redhill, Earlswood (Surrey), Salfords and Horley.
You can plan your journey using the National Rail Journey Planner.
For helpful advice if you need to travel on a rail replacement service, including accessibility and bicycle information, please use our Rail Replacement Services page.
You can find the pick-up and drop-off location of rail replacement services by checking station signage or by searching for your station on our Find a Station page.
Please be advised that replacement vehicles may be busier than usual, and you should allow extra time for your journey.