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 J16 westbound exit | Westbound | Congestion
Sun, 26 Apr 2026 19:21:20 GMT
M4 Current Traffic Incidents
Location : The M4 westbound exit slip at junction J16 . Reason : Congestion. Status : Currently Active. Return To Normal : Normal traffic conditions are expected between 20:15 and 20:30 on 26 April 2026. Delay : There are currently delays of 10 minutes against expected traffic.

M4 westbound between J15 and J16 | Westbound | Congestion
Sun, 26 Apr 2026 17:53:30 GMT
M4 Current Traffic Incidents
Location : The M4 westbound between junctions J15 and J16 . Reason : Congestion. Status : Currently Active. Delay : There are currently delays of 10 minutes against expected traffic.

M4 westbound between J16 and J17 | Westbound | Accident
Sun, 26 Apr 2026 17:30:20 GMT
M4 Current Traffic Incidents
Location : The M4 westbound between junctions J16 and J17 . Reason : Accident involving a vehicle that has left the carriageway. Status : Currently Active. Time To Clear : The event is expected to clear between 19:00 and 19:15 on 26 April 2026. Return To Normal : Normal traffic conditions are expected between 19:00 and 19:15 on 26 April 2026. Lanes Closed : All lanes are closed.

M4 J16 westbound access | Westbound | Accident
Sun, 26 Apr 2026 17:40:53 GMT
M4 Current Traffic Incidents
Location : The M4 westbound entry slip at junction J16 . Reason : Accident involving a vehicle that has left the carriageway. Status : Currently Active. Time To Clear : The event is expected to clear between 20:00 and 20:15 on 26 April 2026. Lanes Closed : All lanes are closed.

M4 westbound between J15 and J16 | Westbound | Congestion
Sun, 26 Apr 2026 17:53:29 GMT
M4 Current Traffic Incidents
Location : The M4 westbound between junctions J15 and J16 . Reason : Congestion. Status : Currently Active. Delay : There are currently delays of 10 minutes against expected traffic.

Map of M4 Motorway Junctions

West M4

East M4

How Do I Find M4 Traffic News?

Latest M4 News