Ashley Gardner is Marion in The Library (Season 3 - Episode 5).
Barbara Alyn Woods is Debby Biblow in The Scofflaw (Season 6 Episode 13).
Barbara Pilavin is the German woman in The Doorman (Season 6 - Episode 18).
Barbara Stock is the attractive subway passenger in The Subway (Season 3 Episode 13).
Berta Waagfjord is Bridgette in The Diplomat's Club (Season 6 - Episode 21).
Billye Ree Wallace is Nana in three episodes. The first, The Pledge Drive (Season 6 Episode 3).
Bobbi Jo Lathan is Patti in 
Brenda Strong is Sue Ellen Mischke in four episodes. Her first appearance was in The Caddy (Season 7 Episode 12).
C.K. Steefel is Kramer's Girlfriend in The Keys (Season 3 Episode 22) and Sylvia in The Cigar Store Indian (Season 5 Episode 10).
Carol Leifer appears in three Seinfeld episodes. The first is The Kiss Hello (Season 6 - Episode 16).
Carol Rosenthal is Ticket Clerck #1 in The Implant (Season 4 Episode 19).