Heilman was 4-4 with a 4.11 ERA and one save in 70 games for the Cubs. The 31-year-old walked 34 and fanned 65 while holding opponents to a .257 average.
"He's a pedigree guy," D-backs general manager Josh Byrnes said. "A former first-round pick with a lot of success in the Major Leagues. He's someone we feel will really strengthen our bullpen."
With the D-backs, Heilman likely will pitch as a setup man for closer Chad Qualls.
"He's pitched in pressurized situations before in terms of his role and the markets he's pitched in," Byrnes said. "He has the stuff to get both left-handed and right-handed hitters out."
Heilman was the 18th overall pick by the Mets in the 2001 First-Year Player Draft and after starting for parts of three seasons, moved into the bullpen. He was outstanding for the Mets from 2005-07, and after an off year in 2008, he was dealt to the Cubs.
In 375 career games with the Mets and Cubs, Heilman is 26-37 with 10 saves and a 4.22 ERA.
The D-backs sent left-handed pitcher Scott Maine and infielder Ryne White to the Cubs. Maine, who pitched in the Arizona Fall League this year, was a sixth-round selection in the 2007 First-Year Player Draft and split time this past season between Double-A Mobile and Triple-A Reno.
White, meanwhile, was a fourth-round pick in the 2008 First-Year Player Draft. Last season, he hit .266 with six homers and 52 RBIs for Class A Visalia.
Along with finding a fourth starter, adding depth to the bullpen was a priority for the D-backs this offseason. With some of the relievers like Rafael Betancourt and former D-back Brandon Lyon expected to get multiyear deals or a lot of money for one season, Heilman provides a little more affordability.
Heilman is eligible for salary arbitration this year after making $1.625 million last season.
Though he seemingly fits the bill of what the D-backs were looking for, Byrnes did not rule out making other additions in the bullpen.
"As I said we may do more in the bullpen, but this is a move that made sense at this point in the offseason for us," he said. "It's still early in the offseason and we'll continue to look at all possibilities for improving our club."
Steve Gilbert is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.