Capill, 51, was sentenced to nine years' prison in 2005 for multiple sex offences against children aged between five and 11, and will be released next month.
He was due for release in June 2014.
In a decision released today, the Parole Board said Capill was not at a high risk of reoffending if he was released early.
It noted he had completed the Kia Marama Programme for child sex offenders.
The Department of Corrections-run programme reduces the risk of sexual reoffending by more than half, according to a Government review.
A psychological report from May also assessed Capill as a medium to low long term risk of sexual reoffending, the board said.
"The psychologist noted that Mr Capill had made progress in intellectually understanding his offending and the salient skills for managing his risk for reoffending...
"We further take into account that Mr Capill has presented well to the Board and it certainly is a contrast to his presentation three years ago."
Capill had previously had five bids for parole denied.
He became eligible after completing two thirds of his sentence in 2008.
His release is conditional on a number of factors, including that he refrains from contact with anyone under 16 unless he is given written consent from his probation officer.
