The veteran defenceman who was a favourite of coach Michel Therrien dating to their junior days in the 1990s was told Monday he would not be offered a contract after attending training camp on a tryout.
The five-foot-eight 195-pound Bouillon, who will turn 39 on Oct. 17, learned his fate at an emotional meeting with Therrien and general manager Marc Bergevin.
The New York native who grew up in Quebe City hopes to find another NHL club and will consider going to Europe to continue his playing career.
"I was ready for both situations," he said, adding that he may have regretted it in the future if he didn't take one last crack at staying on in Montreal.
The Canadiens look ready to start the season with youngsters Nathan Beaulieu and Jarred Tinordi on the blue-line. Beaulieu is expected to play on the third defence pair, while Tinordi will likely be kept as the seventh defenceman.
Bergevin said it was time for the young rearguards, who both spent most of last season at AHL Hamilton, to become full-time NHL players.
"Whoever deserves ice time will get ice time," he said. "We have two young guys. It's time to turn the page for these guys. They need to get better and better."
On Sunday, the Canadiens answered their goaltending question by trading backup Peter Budaj and prospect Patrick Holland to Winnipeg for minor leaguer Eric Tangradi. That gave the job as Carey Price's backup to Dustin Tokarski.
There is still one forward to be cut, but Bergevin said he won't make an announcement until the player is informed. Lars Eller's lower body injury may affect the decision. They still have 19-year-old centre Jacob de la Rose in camp.
Bouillon had two goals and four assists in 52 games for Montreal last season and added two goals in the playoffs.
He signed a free agent with Montreal in 2012 when Therrien began his second stint as the Canadiens head coach, and inked a one-year extension last season. He played in Montreal from 1999 to 2009 before moving to Nashville for three seasons.
Bouillon was captain and Therrien the coach when the Granby Predators won the Memorial Cup in 1996. Therrien sought the undrafted defenceman out when he was coaching the AHL Fredericton Canadiens in 1998-99 and coached him again when he took over from Alain Vigneault in Montreal partway through the 2000-01 campaign.
Bouilon has 32 goals and 111 assists in 776 career NHL regular season games.