Many migrants who arrived here during the immigration boom of recent years are now struggling to find work.
The country gained a record 136,000 new residents in the year ending October 2023
But many of those people - including those whose ability to stay in the country is tied to their employment - have been victims of a softening labour market.
First Union general secretary Dennis Maga said about 25 percent of migrant union members had been affected.
Some were being sent back home on furlough arrangements, he said.
"They are still employed, but the company pays them $100 a month on furlough and will bring them back to New Zealand once construction picks up again."
He said he was also hearing from migrants in the healthcare sector who had been affected by Te Whatu Ora redundancies and hiring reductions.
"A lot couldn't find jobs and are heading back home."
Some had opted to try Australia instead, he said.
Craig Renney, policy director and economist at the Council of Trade Unions, said migrants had fewer of the informal channels for finding work that people who had been in the county longer might use.
"They also may not have access to the formal channels that New Zealanders would have. In addition, rules like the labour market test may make it harder to access to employment," he said.
"Higher skilled migrants will probably continue to find work. Lower skilled migrants - which is more in competition with domestic employees - will probably continue to struggle. Losses in employment are also occurring in sectors where migrant employment is concentrated - retail and construction. We have also seen weaknesses in labour markets in the public sector - which is also a major recruiter of migrant labour."
He said the problem would continue as the unemployment rate continued to increases.
"We might see some strength returning in demand if migration to Australia and elsewhere continues at the pace it has recently."
Kiwibank chief economist Jarrod Kerr said he had also heard that migrants were encountering employment issues.
"One of our clients had a senior engineering job. He got 65 applicants, only 10 were qualified. He said 55 were mostly migrants desperately applying for everything. He said a few sounded quite desperate for work."