Jerry Seinfeld Jerry Seinfeld Actor Julia Louis-Dreyfus Elaine Benes Actor Jason Alexander George Costanza Actor Michael Richards Cosmo Kramer Actor Estelle Harris Estelle Constanza Guest Star Jerry Stiller Frank Costanza Guest Star Heidi Swedberg Susan Ross Guest Star Grace Zabriskie Mrs. Ross Guest Star Warren Frost Mr. Ross Guest Star Jeff Yagher John Guest Star Frances Bay Mabel Guest Star Leonard Lightfoot Clyde Guest Star Don Amendolia Dennis Guest Star Kathryn Kates Counter Woman Guest Star Steve Ireland Music Guy Guest Star Larry David Executive Producer George Shapiro Executive Producer Howard West Executive Producer