M4 J28 Improvement

Scheme outline

Modifications to the existing roundabout at M4 junction 28, which handles interchange movements between the M4 sliproads, the A48 and the A467. The roundabout will be modified to a teardrop shape, with closure of the part between the westernmost entrance and exit, and a new cut-through installed to enable traffic travelling eastbound on the A48 to pass through the middle of the junction. A new section of road will pass around the west side of the flyover carrying the eastbound A48 to replace the closed section of roundabout.

Most approaches to the junction will be widened and traffic signals will be modified to suit the new layout.

In conjunction with this scheme, the Welsh Government will also provide capacity upgrades at the nearby Bassaleg and Pont Ebbw roundabouts.

This scheme was completed in and we're no longer accepting updates or changes to this page.

Junction improvement
with parts under motorway restrictions
Highway authority
Welsh Government


21 August 2017

Construction has been underway since March, with off-peak lane closures and overnight diversions. Work on the new section of road is well advanced, and widening work on the M4 eastbound exit slip (to provide access to the new through route) is ongoing.

25 October 2018

According to the Welsh Government website, new lane arrangements, traffic signals and sections of roadway are due to open this month.

29 November 2018

Work here is now finished.

More information