All 20 district health boards will be affected by the action by the more than 3000 members of the Resident Doctors Association.
The DHBs said they were disappointed an offer they made today had failed to settle the dispute and they were now making contingency plans for hospitals to cope with the strike.
In 2006, a national strike by resident doctors forced hospitals to defer around 17,000 people's appointments for non-urgent surgery or outpatient visits - ranging from heart procedures to children's epilepsy clinic visits. Around 8000 people were similarly affected by resident doctors' industrial action in 2008.
LISTEN: Julie Patterson: DHBs dig in over doctor strike
Association national secretary Deborah Powell said there was now no alternative to strike action in the current dispute.
"It is extremely disappointing it has come to this. However, the DHBs' resistance to meaningfully improve current unsafe rostering practices has left us no choice. We have yet to see sufficient real change in the system after four years of engagement and 10 months of bargaining.
"We see no other way to secure safer rosters for our nation's doctors and the patients we care for."
The association says: "Currently resident doctors work rosters including seven nights in a row and 12 days in a row. The RDA believes this roster is unsafe for patients and unsafe for doctors."
The association wants DHBs to agree to:
• Replace seven nights in a row with a maximum of four nights in a row followed by three days off, and
• Move from 12 days in a row followed by two days off to rosters with a maximum of 10 days in a row and four days off.
The DHBs' spokeswoman, Julie Patterson, said their offer would lead to New Zealand resident doctors, also called resident medical officers (RMOs) "having some of the best hours of work in the world".
"We have agreed to split night shifts that the union reports cause fatigue. We have given an assurance that the maximum number of days worked in a row will be reduced to 10 days and we have provided a framework to fast-track the changes required.
"Despite the DHBs' offer, the union has maintained its position of expecting DHBs to pay the RMOs for the days off that will result from the roster changes.
"We hope the union will at least let the RMOs discuss the DHB offer, before putting the public of New Zealand through the disruption of industrial action."
Powell said the DHBs' assertion her members expected paid days off from the roster changes was "a fairly significant misrepresentation of what's going on. There were claw-backs from the employers as well".
She said money was not an issue. Residents' pay ranges from $28 to $40 an hour and there are no overtime or penalty payments.
The DHBs said their offer included three salary rises, of 1, 2 and 2 per cent, in a three-year deal.
Powell acknowledged residents' hours were better than in the 1980s and 90s, saying: "We probably have some of the best in the world now; it's just that they aren't good enough.
"These guys are up all night. They are doing things we never used to. They are intervening all hours of the day or night ... putting things into people's hearts, dragging out clots. Our guys need to have their wits about them. Frankly, they don't. They are absolutely exhausted."
In a survey of more than 3000 resident doctors, had 1182 identified having made a mistake as a result of fatigue from working long, late hours. And 275 had fallen asleep at the wheel on their way home.
The Labour Party said the strike action was a symptom of Government health "cuts" - funding not keeping up with the growth healthcare costs and demand.
"We know that district health boards are not being funded to keep up with the costs of an aging population, inflation and wages," said Labour's associate health spokesman David Clark.
