Of its 32,000 members who work in DHBs, 83% voted yes in balloting that finished at midday today.
Negotiations had lasted 15 months.
Lead advocate David Wait said he was pleased DHBs took the advice of the Employment Relations Authority after mediation last month and finally put forward an acceptable offer.
"It is great to receive something that both addresses pay issues and makes important progress towards safe staffing.
"Most of the pay increase comes in the form of downpayments on our pay equity settlement, a separate process due for completion by the end of November, but the early lump sum payments are substantial.
"We also have a DHB contractual obligation to safe staffing, with a legally enforceable escalation pathway when members' concerns aren't addressed. Together with new employment commitments these are steps towards addressing the staffing crisis and making nursing an attractive profession again."
The ratified agreement is back-dated to August 1 last year, and will run until the end of October next year.
Wait said members remained wary of their employers' promises, and how DHBs responded regarding safe staffing over the next year would play a big role in the next collective agreement negotiation.
The NZNO had called off strike action set for August following the nationwide Covid-19 lockdown.
Health Minister Andrew Little said he was pleased that there was a settlement that both groups could support.
"This deals with the immediate issue of making sure nurses get a pay rise, but I also acknowledge that we still have to conclude their pay-equity claim.
"Nurses have been under-paid and under-valued for a long time, and the Government is committed to doing something about it."
Nurses were rightly concerned abut staffing levels and action was being taken to recruit nurses into those vacant positions, Little said.
