A ONE News investigation has uncovered immigrant workers who say they are being paid as little as $8 an hour, significantly less than the minimum wage.
Several immigrants who spoke to ONE News said they had found work with employers who offered to help them with residency paperwork, only to be underpaid.
One such immigrant, Avtar Singh, came from India to New Zealand in the hope for a better future.
"I heard about a better pay rate for individuals to earn more money," he said.
Under the Skilled Migrant scheme Singh needed a job relevant to his management diploma.
He approached a small South Auckland supermarket, which took him on as a supervisor.
He signed a contract to be paid $14 per hour, but only rudimentary pay slips show he received only $8 an hour. The legal minimum wage for an adult in New Zealand is $13.50.
"It's not right, but at that time I need the work," Singh said.
When approached by ONE News, the supermarket, which cannot be named for legal reasons, declined an interview but instead send a computer printout of Singh's earnings showing he was paid $14 an hour.
However, when asked for proof of that payment they could not provide it, admitting they had paid him in cash.
Payments in cash were a direct breach of Singh's contract, which states he was to be paid by bank transfer.
Tip of the iceberg
The Department of Labour is currently investigating 95 complaints of payment below the minimum wage.
Employment lawyer Nyra Marshall said it is quite common for complaints of underpayment to be tied up with issues around immigration and visas.
"I fear that we are actually only seeing the tip of the iceberg," Marshall said.
Some people affected by underpayment may be too intimidated or ashamed to come forward with their complaint.
Singh has already found another job managing a different supermarket on more than minimum wage, but the secret economy he has escaped still plays on his mind.
"I don't want any students to suffer these problems," he said.
He said he is speaking out so other immigrants can have a better future.