The ACC minister has announced an independent review into the agency, saying he had concerns with its performance.
Matt Doocey said rehabilitation rates were down, and weekly compensation costs and average costs per claim were up.
"This review will have a particular focus on claims management. It will look at whether ACC has the right interventions and settings in place to support accident claimants to return to independence as quickly as possible," Doocey said.
He would also work with the ACC board and MBIE to strengthen performance monitoring at the entity.
At the same time, Doocey has announced the earners and business levy was having to increase by up to 5 percent a year for three years, to meet the costs of the scheme.
Levies paid by motor vehicles were also increasing by five percent, plus an inflation adjustment per year, for three years.
In dollar terms, it means an employee on a median full-time wage of $70,000, currently paying a levy of $973, will pay $42 more in 2025-26, $49 in 2026-27, and $49 again in 2027-28.
A 500cc motorcycle owner currently paying $297.91 will have an increase of $23.26 in 2025-26, $121.01 in 2026-27, and $90.71 in 2027-28. Discounts will be applied if the owner completes a Ride Forever course.
In September, Doocey had said ACC needed to lift its own performance before charging taxpayers more.