Mr Cliff said while the rate of seat belt wearing in the country was generally very high, people were still dying because they hadn't worn a safety belt.
"If people ... haven't got their seat belts on, they're dramatically more likely to be killed or injured. It doesn't matter where you're seated in the car."
Typically, 60 people who haven't worn a seat belt die in road crashes every year, Mr Cliff said.
While there had been an increase this year compared to last year, Mr Cliff said the road toll was still trending downwards.
"It's certainly nowhere near the rate that it was five or 10 years ago, but what we do say is any death is too many," he said.
Speed was still a factor in many crashes, and the lower speed threshold police put in place over summer and holiday weekends had resulted in fewer road deaths.
"If everyone slows down that has a massive impact on safety," Mr Cliff said.
Modern and safer vehicles also helped the road toll trend downwards.
"We know that road crashes happen for a whole raft of reasons, [but] we know you're going to be much safer in a modern car that's five-star rated," Mr Cliff said.
His comments come after a recent spate of fatal crashes.
A Whitianga man died in a head-on crash in the Coromandel this morning, while a Waikato man died and two other people were injured after a three-car pile-up on the outskirts of Hamilton yesterday.
Today's death wasn't included in the Ministry of Transport's tally.
Two pedestrians were seriously injured in separate crashes today. The first was an 8-year-old girl struck by a car on State Highway 1 north of Kaikoura, and the second a man struck by a car on Breen Rd in Christchurch.
Road deaths January 1 to April 16 2015:
46 drivers
26 passengers
13 motorcycle riders
1 motorcycle pillion passenger
5 pedestrians
2 cyclists
2 other
Road deaths January 1 to April 16 2014:
39 drivers
10 passengers
17 motorcycle riders
1 motorcycle pillion passenger
7 pedestrians
5 cyclists
