Healthcare costs for non-New Zealandcitizens have reached $180 million over seven years.

Unpaid debts for foreigners receiving healthcare in New Zealand has reached nearly $100 million, with another $80m written off as it could not be recovered by district health boards.

Figures released under the Official Information Act showed the total cost of treatment for non-New Zealand citizens across the country's 20 DHBs has reached $199,859,842 since 2007.

Auckland DHB was by far the highest, incurring more than $80m in treatment costs for non-New Zealand citizens since the 2007-08 financial year.

Counties-Manukau came in at more than $38m for the period, and Waitemata spent $19m.

Capital & Coast DHB, encompassing Wellington, recorded spending more than $10m during the period.

Canterbury DHB spent $16m, averaging out at more than $2m a year.

Waikato DHB spent more than $9m.

The figures also showed the amount owed in arrears, and the amount written off at each DHB.

The total amount owed in arrears across the 20 DHBs was $99,571,263. The amount of debt written off since 2007 was $80,358,179.

John Hazeldine, acting director of DHB performance in the National Health Board of the Ministry of Health, said all DHBs had processes in place to identify and charge non-eligible patients.

The DHBs were responsible for seeking to recover debts arising from services to non-eligible patients.

Hazeldine said the ministry recognised debt-recovery was not always possible, and compensated the DHBs with a higher level of debt write-off through its funding.

NZ First leader Winston Peters said it was a "massive" amount being spent on non-citizens, with a large amount of taxpayer dollars going unrecovered.

"It's either been written off because it's never going to come back, or it's outstanding to a level that you can see it being written off in the future, or at least a serious proportion of it."

Peters said visitors to New Zealand should carry their own private insurance.

"We're not requiring people to get off a plane with a simple health insurance policy, which means the costs are imposed upon us."

There was no doubt New Zealanders were missing out on healthcare because of the amount spent on foreigners, Peters said.

"When you see hospitals around the country having to fundraise to try and keep themselves going, it's simply not fair go.

"It's unfair, and nothing is being done about it."

The ministry website says those eligible for publicly funded health services are all permanent residents, and people with a work visa valid for a minimum of two years at the time of issue.

That eligibility also includes a person's partner and children aged 19 and under.

Reciprocal agreements also exist with Australia and Britain to provide certain services.

Other groups of eligible people include refugees.

Health Minister Jonathan Coleman did not respond to requests for comment.

The ministry's website says the Government "strongly recommends that people who do not meet the eligibility criteria take out comprehensive medical insurance".

"People who do meet the eligibility criteria decide for themselves how much coverage they personally want above and beyond publicly funded services."

Public healthcare services include free treatment at hospitals and 24-hour accident and emergency clinics.

Most laboratory tests and X-rays were included, as was free specialist care when referred by a general practitioner, and prescription medicines were subsidised. Free child immunisations and healthcare during pregnancy and childbirth were included.

Children were eligible for free prescription medicine if under the age of six, subsidised visits to the doctor, and free basic dental treatment while at school.

Total cost of treatment for non-New Zealand citizens by DHB since 2007.