Officials say WOF changes will result in more fatal crashes - but be worth it
Wednesday, 10 June 2026
The Government’s upcoming changes to Warrants of Fitness (WOF) requirements will result in an increase in fatal crashes ‒ but would still be worth it, according to official advice.
WOF timelines are being extended out for light vehicles from the end of this year.
New cars will now need their second WOF after four years of driving, not three years, and cars between four and 14 years old will need a WOF every two years instead of every year.
Recently released advice from the Ministry of Transport showed officials were generally supportive of the change, despite assessing they would result in an uptick in crashes due to a higher number of defective vehicles.
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'While the changes are expected to make the system more efficient, they do increase the risk [of] vehicle defect related crashes,“ the officials wrote.
'Our modelling shows costs to road users, NZ Police, medical organisations and insurance companies from increased minor and serious injury crashes and fatal crashes of between $351m and $776m over the next 30 years,' the officials wrote.
They noted that when WOFs were last reformed in 2014 there had been a “statistically significant increase” in crashes where vehicle failures were a contributing factor.
But the officials said the efficiency benefits of allowing people to go longer without a WOF easily outweighed the potential increase in crashes, with a net benefit monetised at $2.6 billion to $4.1b over the next 30 years.
'It is important to note that the estimated net benefit is so significant that even if costs are much higher than expected or most benefits are not realised, the proposed change will still be net positive,“ the officials wrote.
When launching the policy, ministers suggested modelling showed there could be a 0.6% to 1.3% increase in defect-related crashes.
Associate Transport Minister James Meager said he was comfortable with the change.
“Modern vehicles are significantly safer and more reliable, and our current inspection settings impose unnecessary cost and time on motorists. These changes simply better align inspection effort with real safety risk, which is with older and higher-risk vehicles,” Meager said.
“It also brings us more into line with other international jurisdictions such as Ireland, Germany, Japan, and Australia, which inspect every one to two years or at ownership change and achieve comparable or better safety outcomes.”
He said the modelling was deliberately conservative and in reality there were usually many factors at fault in any crash.
“Alongside the changes to inspection frequency, we are increasing penalties, including higher infringement fees for expired warrants and unsafe tyres, so that motorists have strong incentives to keep their vehicles roadworthy even as inspection frequency changes.”
Meager said the Government would monitor the policy after implementation and could change it if it saw a statistically significant increase in crashes with a vehicle defect at fault.