Charities and budgeting services have warned that some families will struggle with back to school costs as schools begin to reopen next week.
The Salvation Army is expecting a spike in applications for loans for digital devices such as computers and KidsCan has 2,600 children on its waiting list for assistance.
School websites show that many are asking for donations and course fees totalling hundreds of dollars per child.
Many also expect students to have a digital device - often a laptop-style computer costing $300 or more - and uniform and stationery bills can also run to hundreds of dollars.
Parents said they expected to pay more than $1000 per child attending secondary school, while those with children at primary schools estimated costs of about $300 including voluntary donations.
The KidsCan charity pays for shoes, uniforms and other school costs for children at 700 schools.
Its founder and chief executive, Julie Chapman, said some children would not return to school on time this year because their families would wait until they had enough money to pay for books, uniforms or food.
"There are some children in New Zealand right now who will not start school when it goes back because their families will keep them home because they're embarrassed that they're unable to provide those things that the school requires of them."
Ms Chapman said KidsCan had 19 schools on its waiting list seeking help for 2600 students and schools were increasingly aware of the financial difficulties some families were experiencing.
"Schools are recognising that increase in hardship, seeing the impact that it's having on children and their ability to learn and looking for ways to get those things like shoes, clothing, food etc into the hands of children directly so they have a better opportunity to learn at school."
The co-ordinator of the Salvation Army's community finance programme, Jodi Hoare, said it was expecting a surge in inquiries from people wanting loans so they could buy computers for school.
They were generally about $300 to $400, she said.
"It's a big burden for people, particularly if they have more than one child that they're trying to get them for in the one year."
Secondary Principals Association president Mike Williams said principals were aware that more families were finding it harder to make ends meet.
He said schools did not want children to miss out on their education and they could help.
"My advice to parents is talk to your school. Most schools that I know of have a hardship fund where they can help, they have some strategies, quite a few have a friendly charity here or that that can help on things.
"Work and Income can help people on benefits. There are lots of strategies."