Speed was identified as a leading factor in 25 per cent of crashes last year.
"That's down from 29 per cent in 2011, but it still accounts for a quarter of crashes - and that's got to come down."
Research had found that on the open road, the number of road deaths fell by about 4 per cent for every1km/h reduction in mean speed.
Mr Bridges said authorities were focusing on public awareness campaigns, aligning speed limits to match road network conditions and increasing the use of speed cameras.
The percentage of motorists speeding in urban areas dropped from 59 per cent to 53 per cent, while similar drops were also recorded among heavy vehicles on our roads.
The figures also show a vast improvement on rates in the mid-1990s, when more than half of drivers broke the speed limit on open roads and more than 80 per cent in urban areas.
Superintendent Carey Griffiths, national road policing manager, believed driver behaviour had changed significantly in the past two decades.
"When we think of ourselves as drivers, we used to drive at 10km or 15km over the speed limit because you could, and you never perceived the personal risk to yourself - now people have slowed down," he said.
"We've still got people who are prepared to do high speeds, but there are less of them, and the reports back from holiday motorists are that there is less speeding behaviour going on around them."
Road tolls from the past two years had been the lowest in 60 years, and this summer's holiday toll was also a record low.
But despite improvements, many motorists were still not getting the most basic message about speeding.
"It's speed that determines whether you walk away from a crash, no matter what the cause is," Mr Griffiths said. "It's still not time for anyone to be complacent - it's still a factor in around a third of our fatal crashes."
There was also a clear link between vehicle speed and the severity of injuries suffered by others in crashes, among them other drivers or passengers, pedestrians and cyclists.
"Basic physics means the lower the speed of impact the lower the crash forces that are ultimately absorbed by fragile human bodies," NZ Transport Agency chief executive Geoff Dangerfield said.
"More people are aware that driving at high speeds is dangerous ... but there are still too many drivers who choose to travel at unsafe speeds."