The motorway will be shut in both directions between Junction 10 (Wisley) and Junction 11 (Chertsey) from 9pm on Friday, March 7, until 6am on Monday, March 10.
This is part of the £317 million M25 Junction 10 improvement project, which aims to ease congestion and improve safety at one of the motorway’s busiest and most dangerous junctions.
Where the M25 will be closed and how traffic will be affected
- The M25 will be closed in both directions between Junction 10 (Wisley) and Junction 11 (Chertsey).
- All entry and exit slip roads at Junction 10 will also be shut during the closure period.
- Nearby A-roads, including the A3, A245, and A320, are expected to be heavily congested.
National Highways is urging drivers to avoid the area unless travel is absolutely necessary.
Why the M25 closure is happening and what it means for drivers
The closure is required to demolish a bridge as part of the ongoing upgrade works at Junction 10.
Junction 10 is one of the busiest and most dangerous sections of the M25, used by around 300,000 vehicles a day. It regularly sees long traffic queues and delays due to its outdated design.
The upgrade project, which started in 2022, is designed to:
- Ease congestion by increasing the number of lanes at the junction.
- Improve safety by redesigning entry and exit points to prevent bottlenecks.
- Enhance pedestrian and cyclist access with new footbridges and crossings.
Jonathan Wade, senior project manager at National Highways, said:
“We know that closing the M25 for an entire weekend is frustrating for drivers, and we wouldn’t do it unless it was absolutely necessary. But these works will make a real difference in the long run by cutting journey times and making the junction much safer.”
The project was originally due to finish in summer 2025, but severe weather in 2024 delayed some elements of the work. The completion date is now set for spring 2026.
The official diversion routes and what drivers should expect
For those who must travel, National Highways has set out signed diversion routes:
- Clockwise (Junction 10 to Junction 11)
- Exit at J10 and take the A3 northbound towards Painshill.
- Follow the A245 through Byfleet and West Byfleet.
- Continue onto the A320 to rejoin the M25 at J11 (Chertsey).
- Anticlockwise (Junction 11 to Junction 10)
- Exit at J11 and take the A320 southbound.
- Follow the A245 through West Byfleet and Byfleet.
- Join the A3 southbound at Painshill to rejoin the M25 at J10 (Wisley).
Drivers are being warned that these routes will be busy, and delays are likely.
National Highways is urging motorists not to rely on satnavs, as they could direct drivers onto unsuitable minor roads, causing traffic problems in residential areas.
Jonathan Wade added:
“We’ve carefully planned these diversion routes, and we strongly encourage drivers to stick to them. Satnavs may suggest shortcuts through local roads, but these routes aren’t built for high volumes of traffic and could lead to even longer delays.”
For longer journeys, using the Dartford Crossing or switching to alternative transport could be a better option.
Another full M25 closure will happen later this month
National Highways has confirmed that another full weekend closure of the M25 will take place later this month for further bridge demolition work.
- The M25 will close again between Junction 10 and Junction 11 from 9pm on Friday, 21 March, until 6am on Monday, 24 March.
- The same diversion routes will apply.
Steve Gooding, director of motoring research charity the RAC Foundation, said:
“Drivers have had to put up with disruption on this stretch of the M25 for a long time, and unfortunately, it’s not over yet. But if the work delivers what’s promised – smoother traffic flow, fewer delays, and a safer junction – then the inconvenience will be worth it. In the meantime, motorists should plan ahead and avoid non-essential trips through the affected area.”
How the closure will affect travel to Heathrow and Gatwick airports
Anyone travelling to or from London Heathrow or Gatwick Airport should allow extra time, as the closure will affect major travel routes.
Several National Express coach services will also be impacted. While they will continue running, delays are expected. The following routes will be affected:
- 025 (Worthing – London via Brighton, Gatwick, Heathrow)
- 200 (Bristol – Gatwick via Heathrow)
- 201 (Swansea – Gatwick via Cardiff, Bristol, Heathrow)
- 205 (Poole – Gatwick via Bournemouth, Southampton, Heathrow)
Passengers are advised to check www.nationalexpress.com/liveserviceupdates for real-time information.
A spokesperson for National Express said:
“We’re working closely with National Highways to keep our services running, but passengers should expect longer journey times, particularly on routes serving Heathrow and Gatwick.”
What drivers should do if they need to travel during the M25 closure
With the M25 set to be heavily disrupted, drivers are urged to:
- Avoid travelling unless absolutely necessary.
- Use the official diversion routes and allow extra time.
- Check live traffic updates before setting off.
- Consider alternative transport, such as trains, where possible.
Rhydian Jones, car insurance expert at Confused.com, said:
“Part of the UK’s busiest motorway will be shut for an entire weekend, and another closure is coming later this month. Drivers should think carefully before setting off. If you must drive, allow extra time, check for delays, and be prepared for queues. If you have a flight to catch, leaving much earlier than usual is a must.”
While the closure will cause delays, National Highways insists that the works are necessary to improve the motorway for the long term.
Jonathan Wade said:
“We’re nearing the final stages of the project, and we appreciate drivers’ patience while we complete these vital improvements. We know it’s disruptive, but once the work is finished, journeys will be much smoother and safer for everyone.”
