Putz can make another $3.25 million in incentives, but that figure is based on him closing games all season. Putz, who was the closer for the Seattle Mariners from 2006 to 2008, signed a free-agent contract in 2008 with the New York Mets before being released last season. He went 1-4 with a 5.22 ERA in 29 games with the Mets.
Putz is rehabbing an elbow injury. He had bone spurs removed from the elbow last season, limiting his only season in New York.
The White Sox have watched him pitch extensively in Phoenix, as have upwards of 10 teams.
"We've been on this for quite some time," White Sox general manager Kenny Williams said. "We've been monitoring him ever since the season ended. His daily workouts we're very familiar with. We've had weekly progress reports. When our doctors finally got their hands on him he passed his physical with flying colors. We couldn't be happier with what was communicated to us by our doctors.
"We feel now from the top of the rotation to the bottom of the bullpen we're as strong as we've ever been."
If Putz makes it all the way back to his previous form, when he saved 36 and 40 games in 2006 and '07, respectively, the White Sox will have a right-handed set-up man to go along with lefty Matt Thornton.
This also gives the White Sox an alternative if they decide to trade closer Bobby Jenks, who is scheduled to make approximately $7.5 million via arbitration.
The Cubs were also very interested in Putz. Cubs scout Brad Kelly watched Putz pitch in Arizona on Wednesday and was scheduled to watch him again Friday before the signing took place.