The contract will pay him $750,000 in the major leagues and $250,000 in the minors.
Thursday's deal, which avoided salary arbitration, is not guaranteed.
The Red Sox acquired Saltalamacchia, 25, from the Texas Rangers before the trade deadline on July 31. Boston general manager Theo Epstein gave Texas two minor league prospects, a player to be named and cash in order to land the switch-hitting catcher. Saltalamacchia went 3-for-19 (.158) with three doubles, an RBI, two runs scored and six walks in 10 games with Boston.
He had season-ending surgery to repair an injured left thumb on Sept. 28. Before the surgery, Saltalamacchia appeared in six games behind the plate with the Red Sox, including five starts. He also played two games for Texas this season, including Opening Day, and combined to hit .248 (68-for-274) with 12 homers and 39 RBI in 72 Triple-A contests between the Rangers and Red Sox organizations.
Information from The Associated Press was used in this report.