Tauranga school principals say the announcement of a new charge for police vetting is yet another cost to add to their already stretched budgets.
The police plan to charge nearly $10 per person for vetting will not come into force until later this year.
There will be exemptions for schools and businesses making 20 or fewer vetting requests per year, and charitable trusts will not be charged anything.
Gate Pa School sends its students on a three-night camp every other year, taking between 25 and 30 parent helpers who have to be vetted - an added cost of about $250 to $300.
Principal Richard Inder said it was just another cost on top of all the other expenses of running a school.
"Schools all over the country are running tight budgets with no operational cost increase this year.
"We wouldn't dream of charging them to have a police vet done, they are already giving up their own time to be available," Mr Inder said.
He said the school would have to rely on charities and TECT funding to pay the extra charges.
"Maybe as this is an election year the Government will increase school's operational costs in the Budget."
Gate Pa School's next camp was in February next year so asking parents to come in to be vetted before the charge came into effect was not a viable option.
He said vetting usually took about 20 days so hopefully if schools had to now pay police would be able to vet people more quickly.
Mount Maunganui College principal Russell Gordon said his school would be using the system and getting as many people as possible vetted before the new charge came into effect.
The school vetted coaches, team managers, teacher aides and some parents.
After the charge was in effect, the school would try to vet fewer than 20 people a year to avoid costs.
"I hope it all works like that," Mr Gordon said.
"The charge of $8.50 a person does not seem like a significant cost but it's a dripping tap effect, it's just something else we have to fit into an income that is not increasing."
Omokoroa No 1 School principal Chris Broadhurst said it would not seriously affect his school as it did not vet every volunteer.
The school took its Year 8 students on a skiing trip with 32 adults.
"The logistics of vetting 32 adults would be nightmarish and paying $320 would be ridiculous," Mr Broadhurst said.
Police Minister Paula Bennett said New Zealand was joining a majority of countries in the world who charge for vetting - in Australia, the charge was about $50 per person.
Demand for vetting has grown in recent years. Since 2011/12 the number of vetting requests to police had increased by 39 per cent to 550,000 in 2015/16.
Labour, the Greens and New Zealand First voted against the legislation passed in November to allow police to charge for vetting.
- schools will be charged $8.50 per person for vetting
- a police vet is a search of the NZ police database for information and provides a criminal history and other relevant information