The next round of work near Gundagai will involve rebuilding the road surface and upgrading safety barriers along the highway's southbound lanes from the Sheahan Bridge to 500 metres south of South Street.

Transport for NSW regional director Cassandra Ffrench said $12 million had been invested into upgrading a 15-kilometre stretch of the Hume south of Gundagai since 2021.

Ms Ffrench said a further $6 million was being spent on the latest stage of the project, which would fix a section of damaged and aged road surface that had high maintenance costs.

"These repairs will not only reduce these costs but also provide a stronger, smoother and safer road surface on the Hume Highway, which will benefit the 12,000 motorists who use this section every day," she said.

The work is set to start on Monday, February 5, and should be completed by late April.

Changed traffic conditions will be in place.

"To limit impacts to motorists, the work will be split in two parts with the first focusing on the southbound carriageway between Middle Street and Jessops Lagoon Road," Ms Ffrench said.

"Transport will close the southbound carriageway with all southbound traffic diverted to the northbound carriageway under two-way lanes."

During this work, the only access into South Gundagai from the highway will be via Middle Street, with South Street access restricted to vehicles exiting South Gundagai to the Hume Highway's southbound carriageway.

Once the first section has been completed, crews will move to the southbound carriageway between Sheahan Bridge and Middle Street, which will involve single lane closures and reduced speed limits.

Work will be carried out weekdays from 7am to 10pm and on Saturdays from 8am to 1pm.

Reduced speeds of 40km/h, 60km/h and 80km/h will apply.

Oversize and overmass vehicles will be required to pull over at the designated heavy vehicle parking bays about five kilometres north of Gundagai on the southbound carriageway and two kilometres south of Gundagai on the northbound carriageway.

Vehicles will be required to call the UHF number listed on electronic signage before entering the work zone.

Motorists have been urged to drive to the conditions and follow the directions of signs and traffic control.

For the latest traffic updates download the Live Traffic NSW App, visit livetraffic.com or call 132 701.