M25

M25 Junction 23: Bignells Corner (A1(M), A1, A1081)

Map of M25 Junction 23: Bignells Corner — M25 Junction 23: Bignells Corner. Map data © OpenStreetMap contributors. Map drawing © Corporate Ace Limited.

Junction 23 at South Mimms is where the M25 meets the A1(M) heading north and the A1 heading into London. South Mimms Services is at the junction. South Mimms and Ridge are the villages beside it, and Potters Bar is a little under two miles east. The De Havilland Aircraft Museum is about two and a half miles north-west.

Drivers bound for the A1(M) north, those heading into London on the A1, and anyone stopping at South Mimms Services meet here. Before a long trip north, this page is a good first look.

For the A1(M) north towards Stevenage, Peterborough and beyond, see our sister site A1M Traffic ↗ (opens in a new tab).

Check this junction now: live M25 speed flow map · latest M25 traffic news · M25 serious incidents · M25 accidents

M25 Junction 23 Now: Accidents, Incidents and Roadworks

Live traffic news at M25 Junction 23

Incidents and roadworks between Junction 22 and Junction 24 that we are aware of.

M25 Clockwise Jct 24 Jct 25 lane 4,3,2 closure

PlannedRoadworksClockwise

Time now: Wednesday, 21 October 2026, 21:42 (9:42pm)

21:28 (9:28pm)21 Oct 2026reported 14 min ago

Location: M25 clockwise between J24 and J25
Direction: Clockwise
Lanes closed: Lane closures
Reason: Construction work
Schedule: 22:00 (10pm) Wed 21 Oct 2026 → 05:30 (5:30am) Thu 22 Oct 2026

Forecast - not confirmed

🚧HA scheduled: 22:00 (10pm) Wed 21 Oct 2026 → 05:30 (5:30am) Thu 22 Oct 2026 starts in about 17 minutes · lasts ~7h 30m

This is the news for Junction 23 only, not the whole M25. For the rest of the motorway see all the latest M25 traffic news, the overhead signs and the speed limits in force now.

Updated 21:42 (9:42pm) Wed 21 Oct 2026

Live Traffic Speeds at M25 Junction 23

The speed strip below shows the M25 around this junction, both directions, from National Highways’ live data, checked every five minutes.

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Key

60 mph +50–5930–4915–29under 15

closedM62connecting motorwayA6A road👈M1our site: tap for its map

services, on the side you can reach them

crashincidentqueueroadworksspeed limitspeed shown on the signsstop-startoverhead sign

reported by drivers, which can’t always be relied onconfirmed by National Highways

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Go to our live M25 traffic speed flow map ›

In an emergency call 999. To report a problem on a motorway, call National Highways on 0300 123 5000 (24 hours).

NOTE: The speed flow, overhead sign messages or other information shown on our live traffic speed flow map is updated every few minutes. We cross check the data and aim to provide warnings if there could be a delay or an inaccurate speed reading. There can be occasions, beyond our control, and despite our best efforts where the speed flow could be inaccurate. We cannot therefore guarantee the speed you can expect on any stretch of the motorway is always accurately shown. However we hope you will find our live traffic speed flow map a useful tool in trying to plan your journey. Safe driving.

All the latest M25 traffic news →Live M25 traffic speed flow map →

M25 J23 in Our Records

Incidents here, last 13 days93 collisions, 6 breakdowns or obstructions

Typical time to clear28 minutesthe middle value of 9 cleared

Slowest daytime hour clockwise16:00–17:00average 38 mph (typical 28 mph)

Slowest daytime hour anticlockwise09:00–10:00average 51 mph (typical 51 mph)

Most incidents we recorded at J23 were breakdowns or obstructions; 3 of 9 were collisions. Clockwise, traffic has been running faster than its typical speed, even in its slowest daytime hour (16:00). Anticlockwise, traffic usually keeps close to its typical speed through the day; the slowest hour is 09:00.

Average speed by hour of day at J23

our average, last 11 daysNational Highways’ typical speed

Clockwise

Anticlockwise

Incidents per week at J23

collisionsbreakdowns and obstructions* part week: we started recording during it

The latest 5 here

Tue 20 Oct, 18:11 (6:11pm) Broken Down Vehicle ✓Reported by National Highways
M25 clockwise between junctions J23 and J24
✓ Cleared after about 72 minutes (1.2 hours)
Tue 20 Oct, 14:50 (2:50pm) Broken Down Vehicle ✓Reported by National Highways
M25 clockwise at junction J23
✓ Cleared after about 16 minutes
Mon 19 Oct, 18:22 (6:22pm) Broken Down Vehicle ✓Reported by National Highways
M25 clockwise between junctions J23 and J24
✓ Cleared after about 28 minutes
Fri 16 Oct, 12:21 (12:21pm) Collision ✓Reported by National Highways
M25 clockwise between junctions J23 and J24
✓ Cleared after about 101 minutes (1.68 hours)
Fri 16 Oct, 10:45 (10:45am) Collision ✓Reported by National Highways
M25 anti-clockwise between junctions J23 and J22
✓ Cleared after about 12 minutes

Built from our own records of National Highways’ live data for the M25 either side of J23: speeds from 11 days of five-minute readings, incidents from the last 13 days (we started recording incidents on 09/10/2026). Each incident is counted once. Updated every five minutes.

Junction M25 J23, Bignells Corner
Roads at this junction A1(M), A1, A1081
Nearest town Potters Bar, 1.9 miles east
Junction before J22, The Bell, about 3.0 miles in a straight line
Junction after J24, Potters Bar, about 2.4 miles in a straight line

Around M25 Junction 23: Bignells Corner: Towns and Places on the Map

Map of the area within about 5 miles of M25 Junction 23: Bignells Corner, showing the towns, villages, roads and places to visit — The area within about 5 miles of M25 Junction 23. Map data © OpenStreetMap contributors. Map drawing © Corporate Ace Limited.

Places on the Map Near M25 Junction 23
Place	What it is	From the junction
Moo-land	Attraction	About 1.5 miles south
Hadley Wood	Railway station	About 2.5 miles south-east
De Havilland Aircraft Museum	Attraction	About 2.5 miles north-west
Colney Fields Shopping Park	Shopping	About 3.5 miles north-west
New Barnet	Railway station	About 3.5 miles south-east
Lambs	Attraction	About 5 miles south-west