Map of M4 Motorway Junctions

Map of the M4 motorway junctions.

West M4

To the West the M4 joins the M5 at M4 Junction 20 which heads north to Devon Cornwall and the South West of England.

The Western end of the M4 is in South Wales Junctions 23 to 48. Bridgend is on Junctions 25 to 37, M4 Junctions 44 and 45 for Swansea, Junctions 30 to 33 for Cardiff and Junctions 24 to 28 for Newport.

East M4

At the eastern end of the M4 is London, with Junctions for Slough, Reading, Newbury, Swindon and Bristol on the way to Wales in the West.

How Do I Find M4 Traffic News?

Simply type the search words in the search facility towards the top right of this page and click "search".

M4 eastbound between J18 and J17 | Eastbound | Congestion
Thu, 14 May 2026 22:23:30 GMT
M4 Current Traffic Incidents
Location : The M4 eastbound between junctions J18 and J17 . Reason : Congestion. Status : Currently Active. Return To Normal : Normal traffic conditions are expected between 23:15 and 23:30 on 14 May 2026. Cause : Road traffic collision. Delay : There are currently delays of 30 minutes against expected traffic.

M4 eastbound between J18 and J17 | Eastbound | Accident
Thu, 14 May 2026 21:56:15 GMT
M4 Current Traffic Incidents
Location : The M4 eastbound between junctions J18 and J17 . Reason : Road traffic collision. Status : Currently Active. Time To Clear : The event is expected to clear between 00:00 and 00:15 on 15 May 2026. Return To Normal : Normal traffic conditions are expected between 00:00 and 00:15 on 15 May 2026. Lanes Closed : There are lane closures.

M4 J12 westbound exit | Westbound | Road Works
Thu, 14 May 2026 20:20:47 GMT
M4 Roadworks
Location : The M4 westbound exit slip at junction J12 . Reason : Roadside drains works are planned. Status : Pending. Schedule : From 21:00 on 21 May 2026 to 06:00 on 22 May 2026. Lanes Closed : All lanes will be closed.

M4 westbound between J11 and J12 | Westbound | Road Works
Thu, 14 May 2026 20:20:46 GMT
M4 Roadworks
Location : The M4 westbound between junctions J11 and J12 . Lane Closures : Lanes 1 and 2 will be closed. Reason : Roadside drains works are planned. Status : Pending. Schedule : From 21:00 on 21 May 2026 to 06:00 on 22 May 2026. Lanes Closed : There will be two of four lanes closed.

M4 westbound between J2 and J3 | Westbound | Road Works
Thu, 14 May 2026 20:39:53 GMT
M4 Roadworks
Location : The M4 westbound between junctions J1 and J3 . Reason : Roadworks. Status : Currently Active. Period : from 21:39 on 14 May 2026 to 05:00 on 15 May 2026. Lanes Closed : All lanes are closed.

Map of M4 Motorway Junctions

West M4

East M4

How Do I Find M4 Traffic News?

Latest M4 News