Kolb found Maclin for a 8-yard touchdown with 7:34 left in the first half to give the Eagles a 21-0 lead, and Philadelphia (4-2) went on from there to notch its fourth win in its last five games.
Kolb went 23-of-29 through the air for 326 yards with one interception in an efficient performance while starting in place of the injured Michael Vick for the second straight week.
Maclin caught seven passes for a career-best 159 yards and DeSean Jackson added one rushing and receiving touchdown each before being knocked out of the game with a head injury.
Matt Ryan was held to 23-of-42 passing for 250 yards with two touchdowns for Atlanta (4-2).
Tony Gonzalez caught a pair of TD passes and Michael Jenkins made five grabs for 99 yards in the loss, which snapped the Falcons' four-game winning streak.