George Costanza's net worth is an estimated $1 million. He has earned his wealth through his successful career as a television writer and producer. Costanza has worked on some of the most popular television shows of all time, including Seinfeld and The Simpsons. In addition to his writing credits, Costanza has also appeared in a few episodes of Seinfeld and The Simpsons. He has also lent his voice to a few video games.