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At a glance

🕐 Last verified 11 Mar, 10:05

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StatusCleared
Severity (NH)Severe
RoadM4
DirectionWestbound
RegionSouth West
CountySouth Gloucestershire
Category (NH)Accident
ReportedWed 11 Mar, 08:55
Cleared10:05
Lasted1h 10m
Road typeMotorway
Speed limit70 mph (variable)
Weather☀️ Clear sky
ReferenceREF-23821983

Times are UK time.

What National Highways say

M4 westbound between J20 and J21 | Westbound | Accident

Location : The M4 westbound between junctions J20 and J21 . Reason : Road traffic collision. Status : Cleared.

The official National Highways record of this incident, kept here after the road reopens.

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1 update captured · Cleared

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Recent M4 incidents

182 incidents and roadworks logged on the M4 in the last 30 days, 56 of them serious or severe. Times are UK time.

M4 | Berkshire | Carriageway Closure | DelaysWed 9 Sep, 21:42 M4 | Berkshire | Carriageway Closure | Long Delays 30 minutesWed 9 Sep, 21:42 M4 | Greater London | Carriageway ClosureWed 9 Sep, 01:27 M4 | Gloucestershire | Road Closure | Expect DelaysWed 2 Sep, 22:45 M4 | Wiltshire | Carriageway Closure | Expect DelaysSat 15 Aug, 02:59 M4 | Wiltshire | Carriageway Closure | Expect DelaysThu 6 Aug, 09:35
Every M4 incident

Common questions

Is the M4 closed?

Not because of this crash. It cleared at 10:05 UK time on Wed 11 Mar. See the M4 right now.

What happened on the M4 on 11 Mar 2026?

Crash on the M4 westbound J20 to J21 in South Gloucestershire, reported at 08:55 UK time on Wed 11 Mar. Cleared at 10:05.

How long did it last?

1h 10m, from 08:55 UK time on Wed 11 Mar.

Where can I see everything else on the M4?

The M4 live page shows what is happening now, and the M4 archive has every incident on record.

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