Pau Gasol added 17 points and eight rebounds, Kirk Hinrich scored 14 points and former Phoenix guard Aaron Brooks had 12 points as Chicago ended the Suns’ three-game winning streak.
Butler’s 3-pointer with 1:08 to play gave the Bulls a 99-92 lead, and he followed it up with a dunk with 9.2 seconds left.
Brandon Knight paced Phoenix with 23 points and P.J. Tucker added 20 points and seven rebounds. High-scoring guard Eric Bledsoe had his second-worst shooting night of the season, finishing 7 of 22 while scoring 21 points.