Employers could pay less ACC fees while workers and motorists pay more as consultation opens on the agency's proposed new levy rates.
The changes come as ACC looks to plug a $1.39 billion gap in the amount needed to fund future injury claims.
The revisions on the cards include a decrease in the average work levy rate for employers and self-employed, but the earners' and motor vehicle rates would increase.
The average work levy rate is proposed to decrease from the current rate of $0.67 per $100 of payroll to $0.63 in 2022/23, then an increase to $0.65 in 2023/24 and $0.67 in 2024/25.
The earners' levy is proposed to increase from the current rate of $1.21 per $100 wages to $1.27 in 2022/23, $1.33 in 2023/24 and $1.39 in 2024/25.
The motor vehicle rates is proposed to increase from $113.94 per vehicle currently to $120.20 in 2022/23, $128.83 in 2023/24 and $138.08 in 2024/25.
The proposals mean the average cost of levies for households would rise.
A family with a household income of $85,000 and two vehicles currently pays $24.11 per week. This would increase to $25.44 a week in 2022/23, $26.76 a week in 2023/24 and $28.10 a week in 2024/25.
A family with a household income of $129,000 and three vehicles currently pays $36.36 per week. This would increase to $38.24 a week in 2022/23, $40.21 a week in 2023/24 and $42.22 a week in 2024/25.
However on the business side, a small home construction firm with eight employees earning $70,000 each and a small fleet of six vehicles currently pays $192.85 per week. This would decrease to $166.05 per week in 2022/23, then go up to $171.28 per week in 2023/24 and $177.66 per week in 2024/25 - still below the original rate.
ACC acting chief executive Mike Tully said the changes vary because the balance sheet is different for each levy account, and by law it can't use a surplus in one account to plug the gap in another.
"When we look at the funding for each of the accounts, the self-employed account is over surplus this year so what we are proposing is a decrease in those levies and that just keeps us true to what the legislation allows us to do in terms of each levy account," he said.
Tully said levies had also not kept up with the growing population and number of claims, together with rising healthcare costs.
"We accept around 2 million injury claims a year and the number of those claims have been steadily increasing over this time as New Zealand's population grows and ages," he said.
Consultation on the proposed changes close on 5 October, and a final decision will be made by Cabinet.