Transgender inmates are now able to request a transfer to another prison which matches their identified sex instead of the sex shown on their birth certificate.
Corrections Minister Anne Tolley said this afternoon that New Zealand had decided to follow international practice by introducing a more flexible prison system for transgender inmates.
"If the sex on their birth certificate has been changed, these prisoners will be managed in accordance with their legal sex," she said.
"Transgender prisoners whose sex on their birth certificate has not been changed can apply to be moved into a prison with their identified gender."
The change followed a request from the Ombudsman, and was designed to improve prisoners' welfare while reducing the risks of victimisation and assault.