Speier was 4-2 with a 5.18 ERA in 41 appearances for the Angels, whose historically reliable bullpen has struggled this season. He is due $4.75 million this season and $5.25 million in 2010.
The Angels dropped Speier four days after the struggling reliever gave up three homers in one inning by the Texas Rangers, but general manager Tony Reagins said the move has been contemplated for longer than that.
"We saw Justin's time here coming to an end," Reagins said. "We felt this route would give Justin the opportunity to seek other employment quicker."
Only Jason Bulger and All-Star closer Brian Fuentes have made more appearances for the Angels this season than Speier, who signed with Los Angeles before the 2007 season. Speier struggled throughout last year, going 2-8 with a 5.03 ERA, and has been even less reliable this season.
During one three-game stretch in July, the 35-year-old veteran retired just one of 13 batters. In Los Angeles' loss to Texas on Friday night, Speier yielded homers to Taylor Teagarden, Omar Vizquel and Michael Young in a span of four batters.
Reagins said the Angels' decision to grant an unconditional release would "allow us to do some other things" with the roster spot, though he didn't specify any moves. Los Angeles was involved in trade talks for several pitchers, but didn't swing a major deal at the deadline.
Speier also has pitched for the Chicago Cubs, Florida Marlins, Atlanta Braves, Cleveland Indians, Colorado Rockies and Toronto Blue Jays during parts of 12 seasons in the majors. He is the son of former major league infielder Chris Speier.
"He has sincere passion and loyalty to this organization, and those feelings are mutual," Reagins said.