Which actor played George Costanza on "Seinfeld"?

Jason Alexander played George Costanza on "Seinfeld." George is Jerry's insecure, scheming best friend and one of the sitcom's four central characters.

Alexander played George throughout the series' 1989–1998 run. The character is famous for his constant reversals of fortune: he lies about jobs, relationships, and plans, then invents increasingly elaborate schemes to escape the consequences. His anxieties and selfishness are presented as comic flaws rather than heroic traits.

George was based largely on "Seinfeld" co-creator Larry David, while his surname came from Michael Costanza, a college friend of Jerry Seinfeld. George's middle name, Louis, is a tribute to comedian Lou Costello. The character's fictional career also changes repeatedly, including work with the New York Yankees and Kruger Industrial Smoothing.

Jason Alexander was already an accomplished stage performer when he joined the sitcom. He won a Tony Award in 1989 for the musical "Jerome Robbins' Broadway." Although George is often mistaken for a direct version of Jerry Seinfeld, the character was primarily shaped by Larry David's personality and experiences.