The Highways Agency is restoring the surface of the northbound carriageway, between junction 22 at Witham North and junction 23 at Kelvedon.
Areas of the surface that are uneven or damaged will be repaired.
The northbound carriageway will be closed between junctions 19 and 24 while the planned work is carried out.
Martin Oliver, Project Sponsor for the Highways Agency, said:
The Agency is spending almost £100,000 on improving this vital route for those travelling towards Colchester.
It does require a carriageway closure but this will be overnight when traffic flows are lowest, to minimise disruption to road users.
We urge drivers to follow the diversion route as sign posted so they continue safely on their journeys and to leave extra time for their journeys. The diversion route has been chosen as it is best placed to safely accommodate all kinds of major trunk road traffic, including heavy goods vehicles, and has been agreed with Essex County Council.
The Agency plans to carry out the work between 8pm and 6am from Thursday 20 March for up to three nights, weather permitting.
Road users will be diverted at junction 19 of the A12 at Boreham onto the A130 and travel north via the A131 towards Braintree. The route will then pick up the A120 at Braintree and travel east down towards Marks Tey where users will rejoin the A12 at junction 25.
There will also be a 50mph speed limit at the exit and entry-slip of junction 19 at Boreham.
The southbound carriageway will be open as normal.
Members of the public should contact the Highways Agency Information Line on 0300 123 5000
Journalists should contact the Highways Agency press office on 0844 693 1448 and use the menu to speak to the most appropriate press officer