M27 Southampton junction 8

We're making improvements to the M27 junction 8 and Windhover roundabout.

Start date Autumn 2023

End date TBC

Cost £25 - £50 million

Following the Government’s budget announcement on the 30 October 2024, the M27 J8 Southampton scheme has been cancelled. The scheme was identified as having poor value for money and limited economic benefits for the region.

It’s essential that the schemes we deliver not only offer provide strong returns on public investment but also have valuable and lasting benefits for our customers.

We remain committed to operating and maintaining a safe and reliable road network and will continue to deliver schemes across the region. We will provide further details on the next steps for the projects in due course.

Latest updates

22 June 2023

Public Inquiry outcome

The Secretary of State has not approved our application for Compulsory Purchase Order and Side Road Order powers which would allow us to make improvements to the M27 Junction 8 near Southampton.

We accept the Secretary of State’s decision and will now take some time to review the detailed contents and advice within the Inspector’s Report to determine how best to proceed.

We understand the challenges at M27 Junction 8 and Windhover have not gone away and we remain committed to working with our partners to support our shared objectives for the local area, which are to improve safety and reduce congestion.

See more updates

Project information

Research has shown that the M27 junction 8 has unfortunately had a significant number of casualties, particularly between 2009 and 2011.

Poor air quality associated with vehicle emissions is currently an issue within the local area. The local authorities are keen to make improvements to encourage more sustainable modes of transport such as walking, cycling or public transport in an effort to improve air quality and health.

Congestion at Windhover roundabout is currently caused by a combination of localised peak time traffic (7am to 10am and 4pm to 7pm) and rat-running to avoid M27 junction 8 tailbacks.

The scheme improvements will help alleviate traffic congestion which will benefit the community in terms of better air quality for local residents and support the economy by providing improved journey times for local businesses using the route. The improvements will lead to a reduction in the number of casualties.

The aims of this scheme are to:

support economic growth – contributing to sustainable economic growth by supporting employment and local residential development opportunities
improve connectivity and reduce journey times around M27 junction 8 and Windhover Roundabout
provide a safe and serviceable network – improving the safety record at M27 junction 8 and Windhover Roundabout (60 year look ahead assessment period)
provide a more free-flowing and reliable network – reducing congestion around the M27 junction 8 and Windhover Roundabout and improve journey time reliability and connectivity between east and west of the M27 junction 8 – Windhover Roundabout
provide a safe, accessible and integrated network – delivering capacity enhancements to the M27 junction 8 and Windhover Roundabout, while supporting the safe, accessible use of active travel modes for pedestrians and cyclists
provide an improved environment – seeking to prevent the worsening of air quality by reducing congestion and journey times along the M27 junction 8 and Windhover Roundabout and aiming to mitigate noise impact