The country's major rest home chains are facing a legal battle over pay as the unions representing aged care workers bring proceedings under the Equal Pay Act.
The Service and Food Workers Union (SFWU) and the NZ Nurses Organisation are filing applications with the Employment Relations Authority today against BUPA, Metlifecare, Oceania, Presbyterian Support, Radius and Ryman Healthcare.
The unions claim very low pay is endemic in the residential aged care sector because of the gender of its workers, who are predominantly women.
SFWU organiser Penny Clark said caregivers were signing up to take the cases because they knew they would not be paid fairly until the gender pay gap was closed.
"Kristine Bartlett took a case for equal pay earlier in the year, and even though it's being appealed, we are confident that she'll win. That's why we expect thousands of caregivers all around the country to take cases too.
"An estimated 30,000 women working in aged care have been underpaid and undervalued for too long."
NZ Nurses Organisation aged care industrial adviser David Wait said the cases were just the beginning.
"Over the next year we expect thousands of caregivers in be involved in legal action demanding equal pay.
"The work caregivers and health care assistants do for our vulnerable elderly is incredibly important in our society.
"We will all lose if we don't recognise the value of the work with a fair and decent pay rate that's equal to what would be paid if the sector were male-dominated."
Mr Wait said a big part of achieving equal pay was for the Government to step up and fund residential aged care providers properly.
"We're hoping this legal action will encourage the Government to do the right thing."
Mr Wait said some 400 applications to the ERA had been filed on behalf of hundreds of caregivers at homes around the country - about 200 per union.
The applications were effectively the same as those filed by the SFWU on behalf Lower Hutt caregiver Kristine Bartlett, which resulted in a landmark ruling paving the way for gender pay equality.
In August, the Employment Court found in favour of Ms Bartlett, who argued the $14.32 an hour she was paid by Terranova Homes was a result of gender discrimination under the Equal Pay Act.
The court did not challenge the fact that Terranova paid its four male caregivers at the same rate as its 106 female caregivers, but it ruled that the four male caregivers were not a big enough comparator group to establish whether the low pay rates for the largely-female workforce were discriminatory.
Terranova Homes is appealing the decision, with the case due to be heard in the Court of Appeal in February.
Mr Wait said the unions had asked the ERA to wait for the outcome of the appeal before hearing the new cases.
He anticipated the cases would be heard together, with thousands more workers expected to join the action next year.
Mr Wait said it was not known how much a successful outcome could end up costing the aged care companies, as the appeal would have to be decided before a wage rate could be set.
But a 2010 report by the Human Rights Commission found the cost of paying caregivers the same as DHB-employed health care assistants would be $139 million to $141 million a year.
Mr Wait said the caregivers were significantly underpaid.
"I wouldn't be surprised if the result of Kristine's case is actually that these people should be paid more than health care assistants with the district health board."