Clutterbuck (24), the club player of the year in Dunedin for the past two years, is returning to his family roots.
He said it was a career-oriented move rather than anything to do with rugby.
Clutterbuck, who will complete his commerce degree - provided he passes his final four exams - at the end of next month, said it was time for a new stage in his life.
The loose forward has impressed for Alhambra-Union, leading the side to championship banners last year and in 2006.
Many felt he should have been given a chance to play for Otago, but he was not selected for either the senior side or the B side.
Clutterbuck said he had no hard feelings about failing to crack the Otago side, and said his career in the south might not be finished yet.
"You never know - I could be back down here again," he said.
"But the Otago coaches have always been totally honest with me about what I needed to do. I think I got a fair go.
"They gave me areas to work on and improve. But it is hard to make it down here.There are some class players around."
He said the coaches had told him to work hard on defence and other parts of his game.
Clutterbuck must be registered with Northland by the end of May to be eligible to play for the union.
"It was a tough decision to make to leave but it is just the start of the next part of my life."
Clutterbuck's family has a farm in Hokianga. He attended Whangarei Boys High School where he captained the First XV.
He said he did not have a job lined up.
He had been in Dunedin for seven years, first at the Sports Institute of Otago and then the University of Otago, with a break in the middle playing for a club side in Ireland.
Clutterbuck had not signed a contract with the Northland union, nor had he linked with a club, but said he had received plenty of texts from friends in Northland suggesting which club he should join.
He leaves with an impressive record, captaining his club side for more than 50 games, and captaining the Otago sevens team.
He played more than 80 premier games for Alhambra-Union.
Last year he was named the North Otago player of the year, after being loaned to the Heartland union.
