Which Seinfeld character was based partly on Larry David himself?

George Costanza was the Seinfeld character based partly on Larry David himself.

George was created as a foil for Jerry’s fictionalized version of himself, but many of George’s insecurities, schemes, frustrations, and social disasters came from Larry David’s experiences. David co-created Seinfeld with Jerry Seinfeld and served as its main writer and showrunner during much of the early run, giving him an unusually direct influence on the character’s behavior and voice.

One well-known example comes from “The Revenge,” in which George quits his job in anger and then returns the next day as though nothing happened. That storyline echoes an incident from David’s time as a writer on Saturday Night Live. Jason Alexander initially approached George with a Woody Allen-like performance, but after learning how closely the character reflected David, he shifted toward what he described as an imitation of David.

George’s surname has a different origin. It was taken from Michael Costanza, Jerry Seinfeld’s college classmate and real-life friend, who later sued over the character. The lawsuit failed. Thus, George combines details from multiple sources: his personality is largely David-inspired, while his surname honors someone from Seinfeld’s own life.