Ileen Getz is AIDS walk organizer in The Sponge (Season 7 Episode 9).
Ivana Milicevic is Patty, Milos' wife in The Comeback (Season 8 Episode 13).
Jane A. Johnston is Mrs. Gack, Todd's Mother in The Calzone (Season 7 Episode 19).
Jane Leeves is Marla Penny, the virgin, in four episodes. The first was The Virgin (Season 4 Episode 10).
Janet Zarish is Rental Car Agent in The Alternate Side (Season 3 Episode 11).
Janice Davies is Building B in The Cadillac Part 2 (Season 7 - Episode 14).
Janeane Garofalo is Jeannie Steinman in The Invitations (Season 7 Episode 24) and in The Foundation (Season 8 Episode 1).
Jennifer Campbell is Tia Van Kamp in three episodes. The first The Airport (Season 4 - Episode 12).
Jennifer Coolidge is Jody, Jerry's girlfriend in The Masseuse (Season 5 Episode 9).
Jessica Hecht is Lindsay Enright in The Couch (Season 6 Episode 5) and in The Gymnast (Season 6 Episode 6).
Jessica Lundy is Naomi in The Watch (Season 4 Episode 6) and in The Bubble Boy (Season 4 Episode 7).
Jill Gray Savarese is Kissing Medical Intern in The Junior Mint (Season 4 Episode 20).
