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 J17 and J18 | Westbound | Overturned Vehicle
Fri, 24 Apr 2026 18:33:08 GMT
M4 Current Traffic Incidents
Location : The M4 westbound between junctions J17 and J18 . Reason : Accident involving an overturned vehicle. Status : Currently Active. Lanes Closed : There are lane closures.

M4 westbound between J17 and J18 | Westbound | Congestion
Fri, 24 Apr 2026 18:27:30 GMT
M4 Current Traffic Incidents
Location : The M4 westbound between junctions J17 and J18 . Reason : Congestion. Status : Currently Active. Return To Normal : Normal traffic conditions are expected between 19:30 and 19:45 on 24 April 2026. Delay : There are currently delays of 15 minutes against expected traffic.

M4 J15 eastbound exit | Eastbound | Congestion
Fri, 24 Apr 2026 17:34:24 GMT
M4 Current Traffic Incidents
Location : The M4 eastbound exit slip at junction J15 . Reason : Congestion. Status : Currently Active. Return To Normal : Normal traffic conditions are expected between 18:30 and 18:45 on 24 April 2026. Delay : There are currently delays of 10 minutes against expected traffic.

connector at M4 J4/M4 spur (Heathrow) | Eastbound | Congestion
Fri, 24 Apr 2026 17:59:30 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 19:00 and 19:15 on 24 April 2026.

M4 J15 eastbound exit | Eastbound | Congestion
Fri, 24 Apr 2026 18:02:24 GMT
M4 Current Traffic Incidents
Location : The M4 eastbound exit slip at junction J15 . Reason : Congestion. Status : Currently Active. Return To Normal : Normal traffic conditions are expected between 19:00 and 19:15 on 24 April 2026. 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