A prison reform group has welcomed National's new policy to grant release to low risk prisoners with sentences of two years or less if they complete training and treatment programmes.
If elected, National plans to introduce Positive Pathways, a rehab programme, invest an extra $48 million over four years and create and extra 6000 places.
The programme will see prisoners who successfully finish training and treatment eligible for release 10 per cent early.
Those serving more than two years who successfully complete the scheme could see an earlier parole hearing, but early release isn't guaranteed.
Tony Gibb of the Howard League for Penal Reform says the plan is good news for prisoners, who'll have an incentive to get a shorter prison term, the government who'll have a few less prisoners for a length of time, and the inmates' families.
"This is not going soft on crime. This is going hard on education," Mr Gibb told 1 NEWS.
He said 50 per cent of the prisoners in New Zealand can't read and write, and the Howard League teaches these skills in jails.
"If they can succeed at that, if they can go and get their basic learner license which gives them photo ID, the chance of them getting a job goes through the roof," he said.
"It's very important to get just these basic steps. And that's what the Howard League does and we're in every jail in New Zealand."
National's Corrections spokesperson Louise Upston said the party is not making sentences shorter.
"Instead prisoners can serve a greater proportion of their sentence in the community," she said.