Canberra's neighbours across the border will soon join the ACT in driving without warning of mobile speed camera vans.
NSW Transport Minister Andrew Constance said the speed camera signs will go over the next 12 months, bringing the state in line with other jurisdictions.
"This is about changing culture and changing behaviour," he said.
"We've seen it happen with our world leading mobile phone detection program, where the rate of people offending has steadily declined. No warnings signs mean you can be caught anywhere, anytime and we want that same culture around mobile speed cameras."
The ACT does not use warning signs ahead of government-owned mobile speed cameras, however the vans have a clearly marked sign on top.
A Transport NSW research report into mobile speed cameras nationally, said the ACT's mobile vans led to an almost 20 per cent reduction in casualty crashes within 500m of the cameras.
Mobile cameras in every other jurisdiction except Queensland, are unmarked.
"But the Queensland markings are neither bright nor distinctive and up to 30 per cent of the vehicles are unmarked," the report stated.
Mr Constance said modelling from Monash University found the changes to the mobile camera program could save between 34 and 43 lives, and prevent around 600 serious injuries in NSW each year.