He is also known for his recurring role on the Emmy Award winning NBC show Frasier, as KACL station manager Kenny Daly.
He has also appeared on a variety of shows including Everybody Loves Raymond, The Practice, ER, Desperate Housewives, Curb Your Enthusiasm, Modern Family, Veep and The Good Fight.
He has appeared in films such as Heavyweights, Sleepless in Seattle, The Birdcage, As Good as It Gets, True Crime, Ghost World, and Bad Santa.
Off Broadway, he won an Obie Award for his performance in Nicky Silver's play The Food Chain.
McGowan played the character Falstaff in Shakespeare's The Merry Wives of Windsor at San Diego's The Old Globe Theatre in August 2023.