Nearly all New Zealand's prisons are now "working prisons" with inmates putting in 40 hours a week, the government says.
Corrections Minister Sam Lotu-Iiga says by 2017 all of them should be providing industry training or other rehabilitation activities.
"Working prisons help prisoners develop skills, experience and behaviour that will help them to find jobs and stability following release," he said.
"This focus on preparing prisoners for release is part of the government's efforts to reduce reoffending by 25 percent by 2017."
Tongariro/Rangipo, Rolleston and Auckland Women's have been working prisons since December 2014.
Northland, Spring Hill, Hawke's Bay and Otago prisons attainted the status in June this year.
"All other Corrections-run prisons have either implemented their plans or are in the process of doing so," Mr Lotu-Iiga said.