Prisoners will be able to carry on watching television when the switch is made to digital.
The Corrections Department is upgrading its television aerial system in prisons so inmates will be able to watch TV following the digital switchover.
Prisoners are barred from having computers, DVDs or video players in their cells but can have a small TV to watch at any time of the day.
Corrections' General Manager Brendan Anstiss says they are conducting essential maintenance to ensure prisoners can continue to watch free-to-air TV after the digital switchover.
Some prisons including Hawke's Bay, Rolleston in Christchurch and parts of Auckland Prison have already completed the changes.
Mr Anstisssays changes will include providing two dedicated Corrections channels for educational and rehabilitative content in the future.