During the 2006 off-season, Havlát, a restricted free agent, told the Senators that he would only sign a one-year deal so he could then test the free agent market in the next off-season. As a result, on July 9, 2006, Havlát was traded to the Chicago Blackhawks, along with Bryan Smolinski, in a three-way deal that also involved the San Jose Sharks acquiring Mark Bell for Tom Preissing and Josh Hennessy. After the trade, Havlát signed a three-year, $18 million contract with the Blackhawks. As his usual number 9 was retired by the Blackhawks for Hall of Famer Bobby Hull, he switched to 24.
On October 5, 2006, Havlát made his Blackhawks debut in outstanding fashion against the Nashville Predators by scoring two goals and two assists in an 8–6 win. Through the first seven games of the season, he was near or at the top of the League in scoring until he went down with an ankle sprain late in a game against the Dallas Stars on October 20, 2006. He returned to the Blackhawks lineup on December 9, 2006, against the Minnesota Wild, netting two goals and an assist, albeit in a losing effort. Havlát was also selected for the 2007 NHL All-Star Game that season. In April 2007, Havlát suffered a shoulder injury, which required off-season surgery. Despite a first season in Chicago partially marred by injuries, he produced at over a point-per-game pace, with 57 points in 56 games.