The Health Services Union (HSU) has had a significant win in securing a deal with the New South Wales government that will see some of the lowest-paid health sector workers secure a pay rise of up to 8.5 per cent.

The breakthrough came after meetings this morning in Sydney with Health Minister Ryan Park and Industrial Relations Minister Sophie Cotsis.

"What's come out of today's meeting is that the government will write to the HSU today committing to a $3,500 increase into salaries," the union's NSW Secretary Gerard Hayes confirmed after the meeting.

"Where that goes to for a cleaner, a security officer, a wards person, an administration officer is anywhere between a 4.5 per cent and 8.5 per cent increase.

"These are the people on 50 ... $55,000, these are the security officers that get bashed every day, these are the cleaners who kept COVID out of hospitals," Mr Hayes added.

The union had threatened industrial action from Monday, arguing the government's offer of 4 per cent to all public sector workers was inadequate and would not meet the rising cost of living.

"This is an amazing day to get 8.5 per cent while others are getting four, it makes literally the difference between buying bread, buying milk, not being able to buy both."

The union said its demand for changes to salary packaging covering people's personal tax savings had not been agreed to and they will meet with the government to discuss it further over the weekend.

But Mr Hayes has recommended members hold off on industrial action at this stage, they are expected to discuss the next move over the next three days.