The 25-year-old defenseman had 17 points (seven goals, 10 assists) in 69 games with the Blues last season and was a restricted free agent. He missed 13 games from Feb. 9-March 12 with a broken right forearm.
"Joel is a player we'd like to have here for a number of years, and this is the first step in doing that," general manager Doug Armstrong told the Blues website. "He's a big body, he complements our skilled players very well, and has a little bit of nastiness to him."
RELATED: [NHL Free Agent Tracker]
St. Louis selected Edmundson, who can become a restricted free agent July 1, in the second round (No. 46) of the 2011 NHL Draft. He has 41 points (11 goals, 30 assists) in 205 NHL games and seven points (four goals, three assists) in 27 Stanley Cup Playoff games.
"He's a quiet personality," Armstrong said. "He doesn't say a lot, but he has the presence in the locker room and certainly the presence on the ice. The opposition knows when he's playing, and it's nice to have that in your group."
Armstrong said Edmundson should help the defense, which was a strong point last season.
"I think we finished sixth overall in goals against, and that was with a lot of injuries on the back end," Armstrong said. "Given some health this year, this group can only be better than it was last year, and it was a solid group."
The Blues previously agreed to terms with restricted free agent forwards Dmitrij Jaskin and Oskar Sundqvist, who had filed for arbitration. Defenseman Jordan Schmaltz is their remaining unsigned restricted free agent.
