Jenny Inge is Head Waitress in The Chicken Roaster (Season 8 Episode 8).

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).

Jessica Tuck is Bonnie in The Label Maker (Season 6 Episode 12).

Jill Holden is Lisa in The Soul Mate (Season 8 Episode 2).

Jill St. John is Mrs. Abbot (Mickey's mother) in The Yada Yada (Season 8 Episode 19).

Jill Talley is Gail in The Soul Mate (Season 8 Episode 2).

Joan Scheckel is Denise in The Beard (Season 6 Episode 16).

Jocelyne Kelly is Model in The Betrayal (Season 9 Episode 8).

JoNell Kennedy is Secretary in The Nap (Season 8 Episode 18).

Judith Shelton is Sally in The Fusilli Jerry (Season 6 - Episode 21).

Judy Kain is Lorraine Catalano in The Chinese Restaurant (Season 2 - Episode 11).

Judy Kerr is Woman in The Abstinence (Season 8 Episode 9).

Julia Campbell is Lisi, the sentence finisher in The Frogger (Season 9 Episode 18).

Julia Louis-Dreyfus is Elaine Benes in all Seinfeld episodes except The Seinfeld Chronicles (Season 1 Episode 1).

Julia Pennington is Celia in The Merv Griffin Show (Season 9 Episode 6).

Julie Claire appears in 4 episodes, three of them as NBC receptionist, and one as Monk's waitress. The first was The Pitch (Season 4 Episode 3).

June Kyoto Lu is Ruby in The Understudy (Season 6 Episode 4).

Justina Vail is a Amanda in The Bizarro Jerry (Season 8 Episode 3).

Justine Johnston is Mrs. Armstrong in The Letter (Season 3 Episode 20).

Justine Miceli is Nina in The Betrayal (Season 9 Episode 8).

Justine Slater is Melissa in The Van Buren Boys (Season 8 - Episode 14).

Karen Fineman is Gwen in The Strike (Season 9 - Episode 10).

Karen Lynn Scott is «Susie, the Farmer's Daughter» in The Bottle Deposit (Season 7 Episodes 21-22) .

Kari Coleman is Alison in three episodes. The first The Outing (Season 4 - Episode 17).

Karla Tamburrelli is Daphne Bower in The Stand-In (Season 5 Episode 16).

Kate Benton is Woman on the phone in The Chinese Restaurant (Season 2 Episode 11) and Roberta in The Pez Dispenser (Season 3 Episode 14).