Mchenery elected to cross the Tasman after coming close to selection for New Zealand's FIFA U20 World Cup Finals squad back in May.
Despite missing selection, the 20-year old rebounded by securing a PlayStation® 4 NPL Queensland Championship medal win with Pride and a place in the competition's Team of the Year.
Mchenery moves to the Napier-based United after scoring three goals in 45 appearances for Pride over the last three seasons, punctuated by a six-month stint at Brisbane Roar.
He will be joining a Hawkes Bay side which made the New Zealand Championship finals last season and are managed by ex-Everton striker Brett Angell.
Pride coach Graham Harvey said the time was right for Mchenery to chase his dreams of playing for New Zealand.
Mchenery is expected to return to Pride in time for next season, though Harvey said this would be reviewed.
Harvey added Pride would not stand in the way if Mchenery's New Zealand stint lead to an opportunity at higher level.
The Pride gaffer has already challenged Joe Duckworth and Jesse Rigby to work hard next season and make the final step to professional football.
Mchenery, Duckworth and Rigby are among 12 senior players who elected to return to Pride's Championship-winning squad next season, with another 5 promoted from the youth teams.
The squad reports for pre-season in early November minus Mchenery and departing Englishman Sam Fitzgerald.
Harvey said he had no issues with Mchenery missing the bulk of Pride's pre-season.
