M25 junction 25 improvements

Upgrade of junction 25 on the M25 to provide greater capacity.

Start date 2020-21
End date TBC
Cost £25 million to £50 million

Latest updates

  • 07 July 2022

    Project moves into final stages

    As we approach the end of the project, we need to make sure everything is ready for when the scheme officially opens for traffic. Over the next few weeks, we’ll be carrying out surveys, checks and any final bits of work, ahead of fully reopening the road.

    You may have also noticed our site compound has been reduced. Don’t worry, we’re still busy on site, there’s just less of us at this stage of the project.

    We have several closures coming up, to allow us to carry out these checks and work:



    Monday 18 to Friday 23 July
    between 10pm and 5am each night

    M25 clockwise exit slip

    Diversion map

    We’d like to thank everyone for their continued patience while we’ve been carrying out these works.

  • 01 June 2022

    Night closures

    We need to install some traffic management on the network over the roundabout. In order to this safely, we will need to carry out some works under night closures.
    This means, on Monday 6 June and Friday 10 June, we will be closing the A10 north approach to the junction, the northern and eastern part of the roundabout, as well as the M25 eastbound entry slip.
    The closure will be in place from 10pm Monday 6 June to 6am Tuesday 7 June and again from 10pm Friday 10 June, reopening 6am Saturday 11 June.

    For customers looking to enter the M25, please follow Winston Churchill Way and the A121 to junction 26, where you can pick up the motorway in both directions.

    For customers looking to access the A10 southbound, please follow the below local diversion of Winston Churchill Way and Monarchs Way to reach the A10, south of the junction:

  • 26 May 2022

    Scheme update - May 2022

    Following our full weekend closure at the beginning of May, we’ve now successfully installed and tested the new traffic lights on the junction. We’re still working around the junction, as we finish off the subway improvements and tarmac the new footpaths.

    You may see some lane closures on the junction and it’s approaches over the next few weeks, as we carry out barrier repairs and finishing works.

    Helping in the Community

    Four members of the M25 junction 25 team recently spent the afternoon helping out at the Broxbourne Foodbank. They took along food and toiletry donations, to help boost the stocks.

    Over the course of the afternoon, the volunteers helped sort 36 crates of food into date and type order, so they can be easily picked when they are put together to make the food parcels.  They also helped pack dozens of food parcels, which contain three days of nutritional food and other items, such as toiletries, cleaning products and baby items for people in need.

    The Broxbourne Foodbank are part of the Trussell Trust and are working to combat poverty and hunger across the UK.

    Broxbourne Foodbank voluneteering

    We’re Excellent!

    Our most recent visit from the Considerate Constructors Scheme (CCS) again rated our site as excellent, after we improved upon on our last site visit scores. We scored top marks in ‘Respect the Community’ category and 14/15 in both ‘Protect the Environment’ and ‘Value their Workforce’.

    The CCS are a not-for-profit, independent organisation who aim to raise standards across the construction industry by ensuring sites registered with them abide by their Code of Practice.

  • 21 January 2021

    Virtual public information event – how to join

    Due to the pandemic and lockdown, we're hosting an online virtual public information event, where you'll be able to view detailed information about the scheme, and ask our project team questions.

    Our team will be available on the following dates:

    Monday 25 January: 8am – 12pm and 2pm – 6pm

    Friday 29 January: 11am – 3pm

    Saturday 30 January: 9am – 12pm

    The link to the virtual room will appear here at 8am on Monday 25 January.

    Join the virtual event


    Project now under way

    We’ve begun preparation works by starting to install our site compound and are building an access track for construction vehicles, with the main construction works to begin in February.

    To keep up-to-date with the scheme progress, please sign up for updates on the right hand side of this page.

  • 24 January 2020

    Detailed design process

    We'll now progress with the detailed design of this scheme through the course of 2020. Scheme construction will then begin in winter 2020-21. Email updates on progression during scheme construction will then be sent to all those who have registered to receive project updates with the scheme webpage.

  • 25 June 2019

    End of Public Information Exhibition period

    The Public Information Exhibition period closed on 24 June 2019.

    The Public Information Exhibition was announced from 20 May 2019 onwards following on from the previous communication milestones. The purpose of the PIEs was to:

    • inform stakeholders of the progress we had made since the PRA
    • describe what would happen next
    • share our initial understanding of potential traffic impacts during construction
    • provide further opportunity to meet the team and ask any questions

    The majority of feedback was regarding the following themes/topics

    • Construction: when the work will start, finish and its duration
    • Discounted options/design decisions
    • How the scheme will operate

Project information

Give us your feedback

Visit our M25 Junction 25 Improvement Scheme feedback tool to have your say. The tool includes an interactive map. You can click on a location to make a specific comment, or give us your general feedback.

ECHO is a one-way feedback tool, so if you’d like a response to your feedback you can email the project team at: M25j25@nationalhighways.co.uk

Junction 25 is a nationally and regionally important road, connecting the M25 with the A10. Up to 6,300 vehicles per hour currently travel through the junction 25 roundabout at peak times, causing congestion and regular delays. The A10 southbound approach into the junction is also a congestion hotspot in Broxbourne.

Our research shows that if we don’t improve junction 25 by 2037, we can expect:

  • increased congestion and lengthy queues and journey times could double
  • average speeds could reduce by up to 30% through the junction
  • disruption would be more widespread following incidents
  • congestion would constrain future development and growth opportunities
  • uncontrolled deterioration to local air quality

Detailed information about the scheme was presented at our virtual engagement event held in early 2021. 

Through this scheme, we aim to:

  • reduce congestion and delays at junction 25 between the M25 and the A10
  • increase capacity by widening both the roundabout and the A10 southbound approach
  • redesign the roundabout to improve safety and traffic flow
  • support future traffic demands, enabling development and economic growth
  • maintain access for pedestrians and cyclists and improve conditions where possible
  • minimise the environmental effects of this scheme on local air quality and noise


Traffic information

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

Sign up for updates!

Keep up to date with what's happening on this scheme by signing up to our updates.