Australian Nursing Federation (ANF) members voted two to one to accept the government's second offer of a three per cent rise.
It came with nurse-to-patient ratios and professional development allowances and leave.
ANF WA secretary Janet Reah said it had been the longest-running enterprise bargaining agreement negotiation in the union's history.
"This was a long and difficult negotiation and campaign and I share the frustrations of nurses and midwives who believe that this isn't enough to remedy the staffing shortfalls in our public health system," she said on Friday.
"Even with this pay increase WA nurses and midwives remain the lowest paid in the country."
Ms Reah said the ANF, which has 40,000 members in WA, and the government should focus on the implementation of transparent and enforceable patient ratios.
The participation rate in the poll was the highest of any the union had previously held.
More than 2066 public sector members voted - almost double the next highest vote in an EBA, which was in 2018 at 1072.
Ms Reah said the union would now focus on the 2024 Public Sector EBA negotiations, which are set to start in a few months.
"The ANF will be seeking a more substantial and fair wage increase in the next round of negotiations which begins in April," she said.
The union had asked for a five per cent pay rise.
It copped a $350,000 fine in May over an illegal strike in 2022 when about 3000 nurses and midwives walked off the job at hospitals across the state.
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