M27 to reopen 24 hours ahead of schedule
The new underpass beneath the motorway has been completed ahead of schedule
Last updated 2nd Jan 2026
The M27 is set to reopen 24 hours ahead of schedule after the completion of a major engineering operation.
A new underpass has been built beneath the motorway using a 'box slide' technique.
Reopening at 4am on Saturday 3rd January, the motorway has been closed between Junctions 9 and 11 since Christmas Eve to enable the construction.
Councillor Lulu Bowerman, Hampshire County Council’s Cabinet Member for Highways, said: “This has been a mammoth engineering challenge, delivered by a dedicated team working around the clock right through the Christmas period.
"The complexity of the operation cannot be overstated – from excavating huge volumes of material to sliding an 8,500‑tonne structure into place and rebuilding the road above it.
"We recognise the inconvenience this has caused for drivers and local residents, and I want to thank everyone for their patience.
"Thanks to the skill of our teams – and favourable weather conditions – construction has progressed smoothly, meaning we can now confirm the motorway will reopen a full day ahead of schedule.
"I’d like to pay tribute to the County Council’s expert team and our skilled contractors, for working 24/7 to achieve this early completion.
"Finishing this phase of the project paves the way for a new, free‑flowing, all‑moves junction due to open later this year, supporting the delivery of the Welborne Garden Village development.
"This showcases what can be achieved when the County Council works closely with its public and private partners on a project of this scale, demonstrating our ability to deliver the infrastructure that underpins sustainable economic growth in Hampshire.”
As the lanes reopen, the 50mph speed limit and lane restrictions that were in place before the closure will remain in place.
Andrew Jackson, National Highways Programme Leader, said: “I would like to thank all drivers and the local community for their patience and understanding while these improvements have been carried out.
"This has been a very complex operation requiring intense planning, teamwork and close collaboration with Hampshire County Council, VolkerFitzpatrick and their construction workers.
"We are delighted to be able to reopen the M27 earlier than planned and are thankful to all those who worked through Christmas to make this scheme a success.”
The £100 million scheme is being delivered by Hampshire County Council and working closely with National Highways.
It's fully funded by the Buckland Group, the developer of Welborne Garden Village and by Homes England.
The underpass is connecting Fareham with the Welborne Garden Village development in the hopes to improve access to the motorway.
The new development's planned to provide up to 6,000 new homes alongside schools and community services.
When open to traffic later in 2026, the underpass will provide two northbound and two southbound lanes connecting with new entry and exit slip roads at Junction 10.
It will also accommodate a shared footway/cycleway connecting Fareham Common to the south and the Welborne Garden Village development to the north.
The two-year construction scheme is due to be fully open to traffic in winter 2026.
Adrian Mawdsley, VolkerFitzpatrick Ltd, Project Director, added: “This is an incredible achievement from our team who have worked around the clock to ensure that the works have been delivered safely and to a high-quality standard.
"The many months of meticulous planning and contingency measures that have been put in place, have meant we are able to open the motorway earlier than expected.
"The successful delivery of this excellent engineering project wouldn’t have been possible without the strong collaboration from our VolkerFitzpatrick staff, Hampshire County Council, National Highways, and our supply chain including Carney Construction, MJ Church, Freyssinet, FM Conway, CP Groundworks and Core Highways.”