Ambulance services are warning that the safety of their patients and paramedics is at risk and more funding is urgently needed.
The country's two ambulance services, St John and Wellington Free Ambulance, rely heavily on public donations and volunteers, with only 70 percent of funding coming from the government.
St John posted a $7.5 million deficit last year, while Wellington Free fell $600,000 short.
This time around, after finishing their annual fundraising drives, both services said they still had huge budget shortfalls.
Paramedics Australasia New Zealand chair Sean Thompson said it had been building for a while, but they now faced a crisis situation.
"We have a core medical provider, staffed by highly trained paramedics, operating as a charity.
"We would not expect our hospitals or the police to operate that way, but that's the service [and] system that we provide for New Zealanders who are most critically unwell," he said.
The way the system operated was no longer safe, he said.
"We're finding that our paramedics are getting stretched, they're getting stressed, they're getting overworked, they operate in a highly demanding environment, and they're getting fewer breaks to get the rest and recuperation that they need.
"So I'm concerned for the safety of the paramedics, but I'm also concerned for the safety of the public who are being attended to by an increasingly stretched service," Mr Thompson said.
Mr Thompson was also a paramedic at Wellington Free Ambulance, and said requirements there had increased significantly over time.
Volunteers were needed to perform similar tasks to those seen in hospital emergency departments at times, he said.
"In the past, we've been a first aid provider who takes people to hospital where the real work is done. But now the real work is also being done in the field.
"So, as an intensive care paramedic, I'm doing medical procedures and providing very powerful controlled drugs that would normally only be provided in hospitals. I'm making some of the decisions that you might expect to be made by a GP," he said.
The government ordered a review last year and a draft report was completed in February. It has since been the subject of review by stakeholders.
'Not going to speculate'
Associate Health Minister Peter Dunne wouldn't say if an increase in funding was on the cards.
"I'm not going to speculate what that might mean, but we're well aware of the concerns of the ambulance sector. We've met with them on a number of occasions.
"I'm keen to ensure we have an effective, competent, and committed ambulance service right across the country, funding is obviously an element in that. But as I say, we're working our way through those issues right now," he said.
Cabinet was likely to consider the report later in the year, and any decisions on it were likely be considered as part of next year's budget.
However, Green Party health spokesperson Kevin Hague said the government needed to stop wasting time and urgently change the model.
"They are an essential health service. It makes no sense at all to have them have to put out the begging bowl to the public in order to be able to sustain their essential service," he said.