M27: Significant delays as Junction 12 interchange is closed this weekend for massive bridge upgrade project
There have been significant delays on the M27 today (Saturday, October 11) thanks to the weekend closure of the motorway’s interchange at Hilsea.
The eastbound M27 has been closed by National Highways at the Junction 12 Cosham / Hilsea interchange this weekend until 6am on Monday, October 13 creating tailbacks on the M27 back towards Fareham as traffic leaves the M27 at North Harbour.
Traffic has also built up around the Cosham area, as well as towards the north of the city with drivers travelling through Hilsea and North End to avoid the M275 and resulting diversion when heading eastbound.
The closure has been put in place to allow for works to continue for the ongoing project to upgrade the bridges at the major interchange which links the M27 with the A27 and the M275. It also impacts traffic heading north on the M275 which would then join the M27/A27 towards Havant.
This weekend’s closure will be followed by a second weekend of eastbound closures from October 17 to 20, and overnight closures from November 3 to 11.

Watch the video embedded in this story to find out more about the project
It follows the recent westbound closures which allowed for the removal of the old road surface and waterproofing, as well as the upgrade of the existing surface drainage.
Emma Weston, project manager at National Highways, said: “Our workforce has made great progress, and we’ve also been very lucky with the weather. We’re hoping that luck continues to hold, as adverse conditions can impact our work schedule – so do check your journey before setting off.
“We are currently working overnight installing the new expansion joints on the westbound bridge and will also install these on the eastbound bridge once the weekend closures are completed.”


Eastbound M27 diversion:
- leave the M27 at J12
- turn right at traffic lights onto A27 Western Road
- take second exit at Portsbridge roundabout to re-join the A27 eastbound
Alternatively:
- follow the M275 southbound towards Portsmouth
- leave the M275 at the Tipner interchange
- take the 3rd exit to re-join the M275 northbound
- bear left toward A27
- turn right at traffic lights onto A27 Western Road
- take the second exit at Portsbridge roundabout to re-join the A27 eastbound
Northbound M275 diversion to join the M27/A27 eastbound
- leave M275 at junction 12 towards A27
- bear left toward A27
- turn right at traffic lights onto A27 Western Road
- take second exit at Portsbridge roundabout to re-join the A27 eastbound
For the latest about the project visit the National Highways website at nationalhighways.co.uk/our-roads/south-east/m27-junction-12-hilsea-interchange-ibm-bridge-repairs