It is the news that thousands of Southampton commuters have been waiting years to hear. National Highways has confirmed that the final lane closures on the M27, which have caused significant delays between junctions 5 and 7, are scheduled to be removed by 6:00 am on Tuesday, 21 April 2026.
For many, it’s the end of a long and frustrating chapter. Since the initial smart motorway works began in 2019, followed closely by the concrete overlay project, drivers have navigated a seemingly endless cycle of narrow lanes, 50mph limits, and overnight diversions. By the end of this month, all four lanes in both directions will finally be open to traffic.
The Reopening Timeline
To reach this milestone, a series of overnight closures are required to remove traffic management equipment and carry out final technology testing. If you are travelling late at night this week, you should be aware of the following schedule:
| Date | Location of Overnight Closure (21:00 to 06:00) |
|---|---|
| 18 April | Junction 7 eastbound entry and exit slips; Junction 8 eastbound exit slip. |
| 19 April | M3 southbound to M27 eastbound link; Junction 5 eastbound entry and exit slips. |
| 20 April | M27 eastbound link to M3 northbound; Junction 5 westbound entry and exit slips. |
| 21 April | All lanes reopened to traffic (Junction 7 westbound exit and entry and Junction 8 westbound entry). |
Speed Limits and Final Testing
While the physical barriers and lane closures are being removed, motorists should not expect to hit 70mph immediately. A temporary 50mph speed limit will remain in place across the newly opened lanes while National Highways completes the final stage of “recommissioning.”
This phase ensures that all sensors, cameras, and electronic signs are communicating correctly with the regional control centre. It’s expected that these temporary speed restrictions will be lifted later in the spring, returning the motorway to the national speed limit once all safety checks are passed.
A Brief History of the Misery
The M27 has been a focal point of infrastructure work for over seven years. The “Smart Motorway” upgrade, which converted the hard shoulder into a fourth permanent lane, was technically completed in 2022. However, the relief was short-lived. Almost immediately, the “Concrete Overlay” project began between Eastleigh and Hedge End to replace the aging, noisy road surface with a smoother, quieter material.
The project has faced several hurdles, including:
- Technology Delays: Testing the Stopped Vehicle Detection (SVD) systems required additional lane restrictions.
- The Hamble Bridge: Essential maintenance and bridge joint repairs often coincided with motorway works.
- Supply Issues: Global material shortages caused several pauses in the construction programme.
What’s on the Horizon?
While the main thoroughfare is reopening, work continues at Junction 10 near Fareham to support the new Welborne Garden Village. However, for those travelling locally between Southampton, Eastleigh, and Portsmouth, the reopening of all four lanes marks a significant improvement in daily journey times.
National Highways has thanked residents for their patience during the works, which they claim will provide “smoother, quieter, and more reliable journeys” for decades to come. As the cones finally disappear, Southampton’s drivers will certainly be hoping that the days of M27 misery are firmly in the rear-view mirror.
Are you looking forward to a cone-free M27? Let us know how the roadworks have affected your commute in the comments below!
