Engineering work is taking place between London Paddington and Ealing Broadway, closing all lines early on Sunday morning.
No trains will run between London Paddington and Heathrow Terminal 5 before 07:25.
The first trains to run will be:
Shuttle train services will run between Heathrow Terminals 2 & 3 and Heathrow Terminal 5.
Check before you travel:
You can plan your journey using the National Rail Enquiries Journey Planner.