About 20 per cent of travel by Canberra drivers occurs in NSW but fatal crashes involving ACT drivers are three to five times more likely to occur in NSW than in the ACT.

According to the report, the majority of crashes occurred on the road to Sydney, near the border, or en route to the coast and in coastal areas. Crashes in these areas accounted for 66 per cent of all fatal crashes involving an ACT driver in NSW, based on vehicle kilometres travelled.

NRMA-ACT Road Safety Trust chairman Don Aitkin said the ACT had recorded the lowest annual road fatalities per 100,000 head of population of all states and territories. ''We have the lowest apparent mortality and morbidity rates on the roads in Australia, way lower than anywhere else,'' Professor Aitkin said.

But ACT drivers are overrepresented in single-vehicle crashes and fatigue and speeding-related fatal crashes on major routes in NSW, particularly at the weekend and during holiday periods. Professor Aitkin said it was important for ACT drivers to remember to take breaks on trips longer than two hours - and this included drives to Sydney.

''Half of our fatal crashes don't occur in the ACT because … the roads are good, there are no or very few heavy trucks, there's very little high-speed driving and there are no rural roads,'' he said.

Professor Aitkin said driver inexperience with unsealed roads might play a role in fatalities.

''The report could not give the reasons for these crashes but obvious candidates are longer trip times and higher average speeds than ACT drivers are used to, as well as unfamiliar gravel roads.''