A12 Chelmsford Colchester roadworks schedule 2026 wraps up this month after months of overnight closures that have reshaped night-time travel between the two towns.
Here’s the essential overview drivers need right now:
- Full scheme runs from 11 May to October 2026 covering junctions 20b–22 and 24–25.
- Work includes resurfacing, central reservation maintenance and fresh road markings.
- Closures have been weeknights only, 9pm–5am, weather permitting.
- Final phase focuses on Old London Road sections with full northbound closures between junctions 19 and 25.
- The National Highways A12 overnight diversion route Essex October 2026 remains active on selected nights this week.
National Highways has treated this as a three-stage job. Stage one hit the northbound carriageway between junctions 19 and 22 from mid-July into early August. Stage two flipped to southbound between junctions 25 and 23 through most of August and September. The last stage brought longer northbound closures from mid-September into October, finishing with the current Old London Road and marking work.
What usually happens on schemes this size is that the official timetable shifts a few days as weather or progress intervenes. That is exactly what occurred here—the final phase slid later than first published. Always treat the published dates as the plan, not a guarantee.
Full A12 Chelmsford Colchester roadworks schedule 2026 at a glance
| Phase | Dates (planned) | Direction & Section | Key Works |
|---|---|---|---|
| 1 | 13 July – 1 August 2026 | Northbound J19–J22 | Resurfacing & markings |
| 2 | 10 August – 12 September 2026 | Southbound J25–J23 | Resurfacing & markings |
| 3 / Final | 14 September – 10 October 2026 (adjusted into early October) | Northbound J19–J25 | Old London Road resurfacing + markings |
| Ongoing restrictions | Throughout | Both directions | 50 mph limits, closed lay-bys |
The final nights of the National Highways A12 overnight diversion route Essex October 2026 sit inside that last phase. Northbound traffic leaves at junction 19, runs the A131 to the A120, and rejoins at junction 25—roughly 23 miles.
Step-by-step plan for living with the remaining schedule
- Bookmark the National Highways project page and the daily closures report. Check both the afternoon before any night journey.
- Note the exact nights still listed: multiple early-October weeknights including 8 and 9 October, 9pm–5am.
- Set your route to follow the signed diversion the moment the closure starts. Do not wait for the app to catch up.
- Build 30–40 minutes into any overnight trip between Chelmsford and Colchester.
- After 5am the main carriageway reopens. Confirm live traffic before you leave at dawn.
- Watch for temporary speed limits and closed lay-bys that stay in place even when the full closure is not active.
In my experience the drivers who treat the remaining nights like a fixed appointment—check once, plan once, drive once—waste the least time. Treat every remaining closure as live until the daily list says otherwise.
Common mistakes on the A12 Chelmsford Colchester roadworks schedule 2026
Relying on last month’s dates. The final phase moved. Fix: open the official daily closures page every afternoon.
Assuming daytime is also restricted. It is not. Daytime traffic runs as normal; only overnight sees the full northbound shut.
Ignoring the diversion signs once you are off the A12. Local roads around the Chelmsford Garden Community and Great Notley fill quickly. Stick to the A131–A120 path.
Forgetting the reverse route for the return journey. Same roads, opposite direction. Plan both ways if you are making a round trip the same night.
Practical advice for the final stretch
Fuel before you leave the A12. Options thin out on the diversion. Keep a close eye on the A131 junctions around Little Waltham and the A120 at Panners Interchange—those spots stack up once the diversion is live. If you travel regularly, set a phone reminder for the last few listed nights so you do not get caught out.
National Highways keeps the live travel alerts and daily closures report as the single source of truth. Local news catches most changes, but the official pages move first.
Think of the remaining schedule as the last few stitches on a long repair job. The road is almost finished; the diversion is the temporary seam that keeps everything safe until the final surface sets.
Key Takeaways
- Scheme runs May–October 2026 with three main overnight phases.
- Final phase centres on northbound closures J19–J25 and Old London Road work.
- National Highways A12 overnight diversion route Essex October 2026 stays active on selected early-October nights.
- Closures are weeknights only, 9pm–5am.
- Always verify the daily closures list—dates can move.
- Daytime A12 remains open throughout.
- Build extra time and follow the signed A131–A120 route.
The real payoff is simple: know the remaining nights, check the official list once a day, and the last stretch of disruption becomes predictable instead of a late-night headache. Next step: open the National Highways A12 Chelmsford to Colchester maintenance page and the daily closures report, then set a quick reminder for any night travel still planned this week.
FAQs
When does the A12 Chelmsford Colchester roadworks schedule 2026 officially end?
The scheme is due to finish in October 2026. The final listed full closures fall in the first half of the month, but always confirm the daily list because weather or progress can add or remove a night.
Is the National Highways A12 overnight diversion route Essex October 2026 still required after the main schedule ends?
Once the final resurfacing and marking nights are complete the full northbound closure and its diversion should lift. Temporary speed limits and lay-by closures may linger a short time longer.
Where is the most accurate source for the remaining A12 Chelmsford Colchester roadworks schedule 2026?
National Highways’ project page for the scheme and their daily road-closure report. Those two sources update first and show any short-notice changes.
