M27 Southampton junction 8

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

Start date Summer 2021
End date TBC
Cost £25 - £50 million

Latest updates

  • 27 August 2020

    August 2020

    The scheme is progressing towards the completion of the preliminary design.

  • 31 March 2020

    Further investigative work

    Now that we’ve announced our preferred scheme we’ll carry out further surveys and investigation to allow us to continue to design the scheme in more detail. Once we’ve completed this work we’ll hold some public events so that you can view the final design and ask any questions you may have.

  • 03 March 2020

    Preferred route

    Following the consultation, we’ve continued to develop the proposed route taking into account issues and alternative suggestions raised during consultation. We’ve also carried out some additional work to establish the solution that provides best value for money. This has led to the scheme being reassessed and we’ve now decided on a joint approach, working with Southampton City Council to deliver the improvements.

    We’ll continue to progress the scheme at the M27 junction 8 and Windhover Roundabout, while Southampton City Council will now deliver improvements at junctions along the A3024 corridor.

    Find out more about our preferred route.

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


Traffic information

Information about scheduled roadworks and events on our motorways and major roads.

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