More than $200 million of the $1.5 billion debt beneficiaries owe the Ministry of Social Development is down to fraud, raising questions about the ministry's oversight.
1 NEWS has been leaked details of the 10 largest welfare frauds as at the end of last year.
The largest individual amount stolen from the ministry that's yet to be paid back is $614,000.
ACT party leader David Seymour is not surprised.
"I'm not surprised one person's done $600,000 of fraud in a culture when the taxpayer has unlimited responsibility and beneficiaries have no ultimate consequences," he told 1 NEWS.
Former Green Party co-leader Metiria Turei became the face of benefit fraud when she admitted claiming payments she wasn't entitled to.
She wasn't prosecuted - but that's not usually the case.
Nine of the ten people with the highest debt have been convicted and sentenced to prison or home detention for benefit fraud as at the end of last year.
Social Development Minister Carmel Sepuloni said, "We don't want to be in the game of prosecuting people. But the reality is we have legal obligations, and where people have done wrong, where they've claimed money where they shouldn't have knowingly then it leads down the prosecution track."
But it's not just fraud, as $729 million is for overpayments and $486 million for 'recoverable assistance'.
National's Social Development spokesperson, Louise Upston, says National "would want to see that MSD are working closely with them".
Ricardo Menendez March of Auckland Action Against Poverty said, "If benefits weren't so low people wouldn't be needing so much additional supplementary assistance to begin with."
The welfare system is now under review and the minister in charge admits it needs work.
"We've got the technology now to try to make things a lot more tighter than what they've been in the past. And we've got to work towards doing that. As a Government we're focused on a fairer welfare system," Ms Sepuloni said.
Mr Seymour says there's only one way to tackle welfare debt and fraud.
"The only way to do this is to have cashless welfare. Give people a card that can be used for select purposes only. Otherwise all you can do is hand out more and more money," he said.
The Government has promised a more compassionate approach, though beneficiaries will have to wait to find out exactly what that means.