Bullock, 32, was acquired by the Spurs in July as a part of a three-way deal that sent Grant Williams from Boston to Dallas. San Antonio also picked up an unprotected pick swap in 2030 in the deal from the Mavericks.
Bullock was in the final year of a three-year contract and was set to make $10.5 million this season. He is now free to sign with any team except for the Mavericks.
The buyout trims down the roster for San Antonio, who now have 16 guaranteed contracts. The Spurs will still need to waive or trade one more of the guaranteed contracts by Oct. 23.
Bullock, heading into his 11th season, averaged 7.2 points last season in 78 games for Dallas while shooting 38.0% from deep.
The Athletic first reported Bullock’s buyout.