If the Rays exercise their option for the 2009 season, Miller will make $2 million. They can buy him out for $400,000.
Miller, 34, pitched for the Rays in 2004 and '05 and gives the team an established left-hander for the bullpen, something the team has lacked since he last pitched for the Rays. He went 3-3 with a 3.57 ERA in 121 appearances with Tampa Bay during his first tour.
"We're very excited [to be back with the Rays]," said Miller, speaking for himself and his family. "From what I've seen, it's a lot different organization from top to bottom."
Miller complimented the work accomplished by Rays principal owner Stuart Sternberg, team president Matt Silverman and executive vice president of baseball operations Andrew Friedman.
"They've done what they said they were going to do," Miller said. "They have a plan. They've stuck to their word. They look you in the eyes and tell you what they are going to do. I respect that."
Miller has pitched the past two seasons with the Astros, for whom he posted a 0-0 record with a 4.86 ERA in 76 appearances in 2007 as left-handers hit just .209 against him.
"I've been consistent [against left-handers]," Miller said. "That's the hardest thing to do in this role is be consistent facing the same guys over and over again in the same division."
The veteran believes he has matured during the past two seasons.
"I'd like to think I'm a little better," Miller said. "[I'm] more seasoned with different angles and breaking balls. I know what I can do physically, know when I need to take a day off."
Miller also is in better shape than during any point in his career thanks to a running regimen that led to his completing his first marathon during the offseason, when he ran the Disney Marathon in Orlando in 4 hours, 27 minutes and 20 seconds.
Signing Miller puts the Rays at 40 players on their 40-man roster.
The team previously signed closer Troy Percival and outfielder/DH Cliff Floyd to address other offseason needs.
Miller becomes the fifth relief pitcher on the Rays' 40-man roster with postseason experience, joining Percival, Dan Wheeler, Al Reyes and Grant Balfour. None of the five were on the club's 40-man at this time last season.
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.