October 2025 M25 and Dartford Crossing Closures: Major Nightly Work in Kent

Overnight closures on the National Highways’s Kent stretch of the M25 and the Dartford Crossing are set to cause some of the most disruptive traffic conditions in years — all happening while most people are asleep. Starting September 29, 2025, and running through October, the agency responsible for England’s busiest motorway will carry out critical maintenance on the Queen Elizabeth II (QEII) bridge, shutting down lanes three and four overnight — leaving just two lanes open for the 180,000 vehicles that cross daily. The twist? It’s not just the bridge. Every major tunnel, slip road, and junction in the area is being touched by work, turning what should be a quiet night into a logistical nightmare for hauliers, commuters, and emergency services alike.

Bridge Repairs and Tunnel Shutdowns: A Nightly Rotation

The National Highways team is tackling structural issues on the QEII bridge’s cable supports — a task that demands precision, darkness, and zero margin for error. Between 9:00 PM and 5:30 AM, Sunday through Friday, lanes three and four are being sealed off. Lanes one and two remain open, but with reduced capacity, slower speeds, and increased congestion. The work is scheduled to last six weeks, meaning drivers will see this pattern for nearly a month and a half.

But the bridge isn’t alone. The Dartford Crossing tunnels are being shut down in a staggered, almost surgical rhythm. The west tunnel closes Monday through Thursday nights from 10:00 PM to 5:30 AM, with Friday and Saturday nights seeing slightly later start times. The east tunnel follows suit on Sundays and alternate weekdays, but with a critical catch: vehicles over 4.8 meters tall are banned from using it entirely during those closures. That’s not just HGVs — it includes motorhomes, delivery vans with roof racks, and even some emergency vehicles with specialized equipment. One logistics manager in Gravesend told us, "We’ve had to reroute three trucks this week already. It’s costing us hours and fuel we can’t afford to lose."

Unexpected Disruptions: M25 Barrier Repairs and M20 Slip Road Closures

While the Dartford Crossing grabs headlines, other parts of the network are quietly falling apart — and being fixed in the dark. From October 24 to 25, 2025, the M25 clockwise between junctions 8 and 9 (in Surrey) will see one of four lanes coned off overnight for emergency barrier repairs. It’s not the biggest closure, but it’s in the wrong place: right where the M25 merges with the M20 and where traffic already slows to a crawl.

Then there’s the M20 westbound slip road at Junction 7. From October 22 to 25, 2025, it’s completely shut from 8:00 PM to 6:00 AM each night. Lanes 1 and 2 on the M20 approaching the junction are also closed. The A249 northbound approach to Junction 7 is blocked too. National Highways has laid out a signed diversion: A249 → A229 → A2 → A249. But anyone who’s tried that route during rush hour knows it’s a 30-minute detour at best — and during these closures, it’ll be longer. "I drive this route for work every day," said a delivery driver from Ashford. "I’ve never seen this many closures at once. I’m thinking about taking the ferry."

October 29–30: The Worst Is Yet to Come

Here’s the kicker: the most severe disruption isn’t the tunnel closures or the bridge work. It’s the resurfacing scheduled for October 29–30, 2025. According to M25traffic.co.uk and m25closures.com, delays of over three hours are expected on the M25 during those nights. That’s not a typo. Three hours. On a motorway that’s already jammed at 5 PM. This work is happening on a stretch that connects Kent to London, the Medway towns, and the Channel ports. It’s the choke point for everything from Christmas deliveries to hospital ambulances.

And it’s not just the surface. Crews are replacing drainage systems beneath the asphalt — a hidden but vital upgrade. But that means cutting deeper, working slower, and blocking more lanes. The noise, the dust, the light — it’s all going to be visible from homes in Swanley and Dartford. One resident near Junction 5 said, "I’ve lived here 22 years. I’ve never heard this much jackhammering at 2 a.m."

What’s Being Done — and What’s Not

National Highways insists it’s doing everything possible to minimize impact. They’ve posted nightly updates, activated emergency access protocols, and even deployed additional traffic officers. But critics point out that the work is being done in isolation — not as part of a coordinated regional plan. "This is the third major closure in Kent this year," said Dr. Eleanor Voss, a transport policy analyst at the University of Greenwich. "They’re fixing one thing while ignoring the bigger picture. If they’d scheduled this with the M20 work, or timed it outside peak freight hours, the damage would be far less."

Meanwhile, the South East Maintenance Schemes — Phase 1 (Sept 22–Oct 11) and Phase 2 (Nov 10–22) — are just the beginning. There’s no sign this will slow down. In fact, the government’s National Infrastructure Strategy has earmarked over £1.2 billion for M25 upgrades by 2030. These October closures? They’re the first visible ripple.

What Drivers Should Do Now

Don’t rely on memory. Don’t trust Google Maps alone. National Highways says closures can change at short notice — and they have, before. On October 15, 2024, a tunnel closure was moved up by 12 hours due to a structural concern. Drivers are urged to:

• Check Traffic England every evening before travel
• Use the National Highways app for real-time alerts
• Avoid the M25 entirely on October 29–30 if possible
• Plan for 90 minutes extra on any journey through Kent during these dates
• Confirm vehicle height if using the east tunnel on Sunday nights

"It’s not about inconvenience," said a National Highways spokesperson in a statement. "It’s about safety. We’re not just resurfacing roads. We’re preventing future collapses."

But for the thousands who depend on this corridor — from nurses heading to Darent Valley Hospital to farmers delivering milk to London markets — safety doesn’t feel like it’s winning. It feels like they’re being asked to pay the price for infrastructure that was built 40 years ago.