Latest live M4 traffic news
Live M4 traffic news and updates for M4 junctions, plus real time travel reports on delays, accidents, roadworks and snow
The M4 is the main road running between London and South Wales, passing via Slough, Reading, Swindon, Bristol, Newport, Cardiff and Swansea along the way. Much like the rest of the UK’s road network, the M4 has its areas most likely to cause tail backs – primarily where it joins the M25 on the west of London and also where it meets the M5 near Bristol. Naturally, accidents, roadworks and other traffic issues cause delays, so it pays to be on top of your journey before you start your engine.
Where the M4 crosses the River Severn at the Welsh end of the motorway, it uses a toll bridge – which is one of only three left in the UK. The tolls are only charged when driving in a westerly direction, meaning drivers are charged to enter Wales, but not to enter England. The original River Severn crossing (the M4 uses the second one built) now carries the M48.
Generally the majority of the M4 tends to stay relatively clear, but the 189-mile route can see extra congestion during rush hour and summer holidays. If you’re planning to use any section of the M4 motorway, this page will be a useful aid for travel alerts, live updates and an incident map for both westbound and eastbound lanes.
Scroll down to find live tweets from the Highways Agency, official police accounts and other traffic news feeds.
M4 live traffic map
If there is traffic disruption on the M4 you can keep up to date on any delays with our live and continuously updated M4 traffic map.
The map below shows live updates on the current disrupted areas of the M4 for roadworks, accidents or general congestion causing delays on the route…
M4 weather report
Details of the latest weather warnings in the M5 area from the Met Office...
The history of the M4
The Ministry of Transport first proposed a new road from London to South Wales in the 1930s. Plans for the M4 as one of the first major post-war trunk roads were produced in 1956 and construction began in 1961. The Chiswick flyover, a short section of elevated dual-carriageway built to reduce the impact of traffic travelling between central London and the west, opened in 1959 and later became part of the new M4 route. The section from J18 to the west of Newport was opened in 1966, including the Severn Bridge, which is now part of the M48.
The English section of the motorway was completed in December 1971 when the 50-mile stretch between Maidenhead and Swindon was opened for public use. The Welsh section was finished in 1993, when the Briton Ferry bridge opened. The Second Severn Crossing opened in 1996, and motorways on either side of the river carried the M4 over the new crossing when construction was finally completed.
All of the M4 junctions on the southbound and northbound carriageways are detailed below...