TSN's Bob McKenzie reports the deal has an average annual value of $1.5 million.
Ballard, 30, has played the past three seasons for the Vancouver Canucks, who used a compliance buyout on the remaining two years on his contract. He had two assists in 36 games in 2012-13.
"I did need a change, so to me, the buyout is a good thing," Ballard told the Star-Tribune before the deal was reached. "In my meetings at the end of the year with management in Vancouver, we all agreed that however it worked out, I needed a change. It's a funny feeling. In a lot of ways I'm very excited, but it's disappointing that it got to this. I'm so excited for the opportunity and what's going to come this next season."
The native of Baudette, Minn., has 165 points (36 goals) in 545 NHL games over eight seasons spent with the Canucks, Phoenix Coyotes and Florida Panthers. He attended the University of Minnesota, and was the 11th pick of the 2002 NHL Draft by the Buffalo Sabres.
"I think for me Minnesota makes sense," Ballard said, "that I’m familiar with the guys, obviously that I live here, that I train with some of the guys during the offseason."