16 Mar 2026
Rail passengers across South Wales are encouraged to plan ahead as essential track work takes place between Newport, Cardiff and the Valleys between Friday 20 to Sunday 22 March.
The work taking place will see Network Rail engineers replacing sections of the track on the South Wales Mainline between Newport and Cardiff Central throughout the weekend, with Transport for Wales (TfW) engineers carrying out further work near Cardiff Queen Street on the Sunday.
These works will affect all services travelling from Cardiff to Newport throughout the weekend, and Valleys services travelling through Cardiff Queen Street on the Sunday. Rail replacement services will be in place and passengers are advised to allow extra time for their journeys.
Colin Lea, Planning and Performance Director at TfW, said: "We’re encouraging all passengers travelling between Cardiff and Newport to check their journey in advance, as many of our services will be affected throughout the weekend. This includes trains to Manchester, Holyhead, Cheltenham, Ebbw Vale, Maesteg and some Valleys services on Sunday.
“To help keep passengers moving, we’ll be running a comprehensive rail replacement bus service. We'll have buses running roughly every five minutes between Cardiff and Newport, with an additional four buses per hour in each direction serving the Valleys blockade.
“Our teams will be on hand throughout the weekend to support customers and help them reach their destination.”
Nick Millington, route director for Network Rail Wales and Borders, said: “The work we’re carrying out between Newport and Cardiff is essential to keeping this busy stretch of railway safe, reliable and ready for the future.
“We understand how important these journeys are for people travelling, and we’re sorry for the inconvenience it causes. Thank you to everyone for your patience and understanding while we complete these essential upgrades.”
TfW encourages all passengers travelling along these routes to check before they travel using the TfW app or website.
Passengers using pay as you go within the Metro are asked to follow these steps:
- TfW staff will be at Newport and Cardiff Central with hand‑held pay as you go validators. If your journey starts or ends at these stations, just tap in or out with the team’s mobile validators, or speak to our gate line staff.
- If you’re travelling through these stations (e.g. Chepstow to Bridgend), do not tap in or out at Newport or Cardiff Central as this may result in an incomplete journey. Tap in at your starting station and tap out at your destination as normal.
- Revenue protection staff will check that you’ve tapped correctly when you get on or off rail replacement services.
- You must have a valid ticket to board the rail replacement buses.
Notes to editors
Cardiff to Newport services
The railway line between Cardiff and Newport will close late on Friday 20 March, with the first rail replacement bus leaving Cardiff Central for Newport at 22:55, and Newport for Cardiff Central at 23:32. This closure will continue throughout Saturday and Sunday.
The following rail services will be affected during the rail closure:
- No rail services will run between Cardiff and Newport.
- Services to Manchester, Holyhead and Cheltenham will start and terminate at Newport. First class and hot food will not be available between Newport and Manchester throughout the weekend.
- Newport to Ebbw Vale services will run hourly on Saturday and every two hours on Sunday.
- Maesteg services will start and terminate at Cardiff Central.
- GWR services to London Paddington and Exeter St Davids will start and terminate at Newport.
- GWR Portsmouth Harbour services will start and terminate at Bristol Temple Meads.
- GWR will run services between Swansea, Carmarthen and Cardiff Central.
- CrossCounty will start and terminate all Cardiff to Nottingham services at Newport.
Cardiff to Newport rail replacement services
Rail replacement buses will run between Cardiff Central and Newport approximately every five minutes, with services connecting into the main station car parks at both stations. Queuing systems will be in place and customer support teams on hand to help.
Cardiff Valley Lines services
Essential engineering work between Cardiff Queen Street and Cardiff Bay on Sunday 22 March will also affect a number of Cardiff Valley Lines services.
The following services will be affected:
- Treherbert, Aberdare and Merthyr services will run to and from Cardiff Central via the City Line (Ninian Park). These services will not stop at Cardiff Queen Street, Cathays or Llandaf.
- No services will run on the Coryton line.
- No services will run between Caerphilly and Cardiff Queen Street. Trains will run as normal between Caerphilly and Rhymney.
- No services will run between Cardiff Queen Street and Cardiff Bay. The half hourly Pontypridd–Cardiff Bay service will not run.
Services between Cardiff Central and Barry Island, Bridgend and Penarth will operate as normal.
Cardiff Valley lines rail replacement services
Rail replacement buses will run on the following routes on Sunday:
- Between Caerphilly and Cardiff Central, stopping at all stations along the route.
- Between Radyr and Cardiff Bay (hourly), calling at Llandaf, Cathays and Cardiff Queen Street
- Between Radyr and Cardiff Central (every 30 minutes), calling at Llandaf, Cathays and Cardiff Queen Street
Ticket acceptance will be in place on Cardiff Bus services operating along the Coryton and Cardiff Bay routes.
