Police say they are putting extra focus on ensuring seatbelts are used after a hike in the numbers killed on New Zealand roads while not wearing restraints.
Deaths involving people who weren't buckled up has nearly doubled in the past two years, a statistic Assistant Commissioner Dave Cliff describes as unacceptable.
"Almost a third of people who die on our roads are unrestrained vehicle occupants and these are all deaths which are entirely preventable," he said.
"We are at a loss to understand why there has been such a massive increase in people not wearing their seatbelts."
In 2016, the seatbelt wearing rate for drivers and adult front seat passengers was 96.5 per cent.
This is a drop from the 97.1 per cent observed in 2014 and is the first time there has been a reduction in wearing rate since 1996
Assistant Commissioner Cliff said it was also a concern that the number of females killed in crashes while not wearing a seatbelt had increased substantially in the last five years.
"All this can be prevented by taking two seconds to put on your seatbelt - it's that easy."
He said a seatbelt reduced the risk of death risk by 50 per cent for those in the front seats and by 75 per cent for back seat passengers.