The decision was seen as a given because Bass' value is viewed as considerably greater than the $4.25 million he would have made next season had he opted into the last year of his deal.
Despite opting out, Bass would still like to return to the Celtics next season under a different contract.
"Oh absolutely," his agent Tony Dutt said when asked if Boston was his client's first choice. "Without question, he would love to go back."
Bass proved himself as a valuable contributor during his lone season in Boston, averaging 12.5 points and 6.2 rebounds, but the Celtics are staring at an uncertain future and its unclear which direction general manager Danny Ainge will head.
"I'm no different than anyone else," Bass told CSNNE.com recently. "I'm going to do what's best for me and my family. Hopefully that'll keep me here in Boston. We'll see."