Around a third of the deportees arriving from Australia served less than a year in jail or haven't been convicted of any crime, the Government says.
New figures released by Justice Minister Amy Adams show of the 105 people that have been sent back to New Zealand since the Government passed monitoring laws last year, 70 percent are being supervised.
Ms Adams said the rest were not eligible for automatic supervision under the law enacted in November, because they were sentenced to less than one year in prison or were deported on "character grounds" rather than because of convictions.
But she said all deportees have had their details and DNA collected.
"I've said throughout that while there is always a risk of reoffending, as there is with any offender who leaves prison, this law goes a long way to mitigate that risk for law-abiding New Zealanders," Ms Adams said.
There's been an increase in the number of New Zealanders being deported from Australia after a change to immigration rules across the Tasman at the end of 2014.
Law changes have been made in New Zealand so eligible offenders can be subject to parole-like conditions on their return.
Last week Corrections Minister Judith Collins announced $100,000 would be given towards a programme helping deportees settle.