A12 Chelmsford to Colchester maintenance

November planned closures

We’re doing essential resurfacing work on the A12 southbound between Marks Tey and Hatfield Peverel over three nights starting Wednesday 4 November 2026, working overnight between 9pm and 5am on weeknights only, weather permitting.

Closures and diversions

To work safely, we’ll need to close the A12 southbound and divert traffic as follows:

• exit the A12 southbound at junction 25 for Mark’s Tey Interchange
• at Princess of Wales Roundabout, take the third exit onto the A120 westbound 
• at the following roundabout, take the first exit onto A120 Coggeshall Road and continue on the A120 towards Braintree
  At Marks Farm Roundabout, take the first exit, continuing to follow the A120 westbound
• exit the A120 at Great Notley Roundabout for the A131
• at the roundabout, take the second exit onto the A131 and continue towards Chelmsford
• at Generals Lane Roundabout take the fourth exit for A12 northbound junction 19 and follow towards junction 25, resuming your journey 

Please note that there will be emergency vehicle access during the work.

Please remember that closures can change at short notice. You can find the latest information on our daily closures page or check for current incidents, disruptions and delays. Our travel alerts give details of high priority incidents on our network.

How to find out more

To find out more about other major road improvements we’re carrying out across the East of England, please visit our website.

If you would like more information, please contact us on 0300 123 5000, or by email at info@nationalhighways.co.uk.