Best known for playing the character Charlie Kelly on the popular FX series It's Always Sunny in Philadelphia, he also created the show and serves as a producer and writer alongside co-stars Glenn Howerton and Rob McElhenney.
He played shortstop on the baseball team at Merrimack College, where he also majored in fine arts. During college summers, he refined his acting at Williamstown Theatre Festival.
One of his first film roles came in the 2010 comedy Going the Distance alongside Drew Barrymore and Justin Long. In 2014, he voiced the character Benny in The Lego Movie.
He married Mary Ellis, whom he met on the set of Reno 911! She also became a recurring character on It's Always Sunny in Philadelphia. The couple welcomed a son in 2011.
He starred in the comedy films Horrible Bosses and Horrible Bosses 2 opposite Jennifer Aniston.