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 westbound between J12 and J13 | Westbound | Vehicle Fire
Sat, 16 May 2026 13:44:10 GMT
M4 Current Traffic Incidents
Location : The M4 westbound between junctions J12 and J13 . Lane Closures : The hard shoulder, lanes 1 and 2 are closed. Reason : Vehicle fire. Status : Currently Active. Time To Clear : The event is expected to clear between 15:45 and 16:00 on 16 May 2026. Return To Normal : Normal traffic conditions are expected between 15:45 and 16:00 on 16 May 2026. Lanes Closed : There are two of three lanes closed.

M4 J3 westbound exit | Westbound | Congestion
Sat, 16 May 2026 13:40:30 GMT
M4 Current Traffic Incidents
Location : The M4 westbound exit slip at junction J3 . Reason : Congestion. Status : Currently Active. Return To Normal : Normal traffic conditions are expected between 14:30 and 14:45 on 16 May 2026.

M4 westbound between J16 and J17 | Westbound | Accident
Sat, 16 May 2026 05:21:12 GMT
M4 Current Traffic Incidents
Location : The M4 westbound between junctions J16 and J17 . Lane Closures : Lanes 2 and 3 are closed. Reason : Road traffic collision. Status : Currently Active. Time To Clear : The event is expected to clear between 07:15 and 07:30 on 16 May 2026. Return To Normal : Normal traffic conditions are expected between 07:15 and 07:30 on 16 May 2026. Lanes Closed : There are two of three lanes closed.

connector at M4 J4/M4 spur (Heathrow) | Eastbound | Congestion
Sat, 16 May 2026 05:44:16 GMT
M4 Current Traffic Incidents
Location : The M4 eastbound exit slip at junction J4 . Reason : Congestion. Status : Currently Active. Return To Normal : Normal traffic conditions are expected between 06:45 and 07:00 on 16 May 2026.

connector at M4 J4/M4 spur (Heathrow) | Eastbound | Congestion
Sat, 16 May 2026 08:34:19 GMT
M4 Current Traffic Incidents
Location : The M4 eastbound exit slip at junction J4 . Reason : Congestion. Status : Currently Active. Return To Normal : Normal traffic conditions are expected between 09:30 and 09:45 on 16 May 2026.

Map of M4 Motorway Junctions

West M4

East M4

How Do I Find M4 Traffic News?

Latest M4 News