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At a glance

🕐 Last verified 14 Mar, 09:05

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StatusCleared
Severity (NH)Severe
RoadM4
DirectionWestbound
RegionEastern
CountyWest Berkshire
Category (NH)Accident
ReportedSat 14 Mar, 07:03
Cleared09:05
Lasted2h 1m
Road typeMotorway
Speed limit70 mph (variable)
Weather☀️ Clear sky
ReferenceREF-24112609
Views130

Times are UK time.

What National Highways say

M4 westbound within J12 | Westbound | Accident

Location : The M4 westbound at junction J12 . Lane Closures : Lane three is closed. Reason : Road traffic collision. Status : Currently Active. Time To Clear : The event is expected to clear between 09:00 and 09:15 on 14 March 2026. Return To Normal : Normal traffic conditions are expected between 09:00 and 09:15 on 14 March 2026. Lanes Closed : There is one of three lanes closed.

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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Also on the M4 today

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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 09:05 UK time on Sat 14 Mar. See the M4 right now.

What happened on the M4 on 14 Mar 2026?

Crash on the M4 westbound at J12 in West Berkshire, reported at 07:03 UK time on Sat 14 Mar. Cleared at 09:05.

How long did it last?

2h 1m, from 07:03 UK time on Sat 14 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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