District health boards have recorded budget shortfalls totalling $54 million - something Labour says shows the increasing stress placed on the health system.
Unaudited Ministry of Health figures released by Labour show 13 of 20 district health boards were in the red for the 2015/16 year.
Annette King, the party's health spokeswoman, said the total deficit was expected to be around $19 m.
"It's blown out to nearly three times that...DHBs say they are in trouble because they are not getting enough money to meet the increase in demand. Two boards have not even been funded to meet their staffing costs.
"This means additional funding boards received in Budget 2016 will be swallowed up by their deficits."
King said the worst budget blowouts were at Lakes DHB, Capital and Coast, Midcentral, Tairawhiti and Taranaki.
"Doctors are already up in arms over work stress and these figures mean things can only get worse before they get better."
Auckland, Counties Manukau, Hawke's Bay, South Canterbury, Southern, Waikato, Waitemata and Wairarapa DHBs all recorded surpluses above their annual approved budgets.
Health Minister Dr Jonathan Coleman said the bigger picture was that DHB deficits were reducing.
"We inherited deficits of $160 million, they are now $54 million. It is a fraction of 1 per cent of the total health budget," he told Radio New Zealand.
Services had improved since National came to power, Coleman said, with more operations and specialist appointments being completed.
If the $35 m deficit recorded by Southern DHB - under the control of commissioners - was removed from the picture then it was "pretty good overall", Coleman said.
The National Government has increased health funding annually since first elected in 2008, but critics say it has not kept up with rising healthcare costs and population pressures.
May's Budget allocated an extra $2.2 billion to be pumped into health over four years to help cope with an ageing population and record immigration.
A large portion of the funding boost will go to district health boards - they will get an extra $400 m in 2016/17.
There was also close to $40 m over four years for a new national bowel screening programme.
In the lead-up to the Budget, CTU economist Bill Rosenberg said DHBs needed an increase in $551 million to maintain the current level of DHB services.