Vanessa (played by Lynn Clark): An attractive woman that Jerry meets at a birthday party in "The Stake Out" (Season 1, Episode 2). They date once in "The Stock Tip" (Season 1, Episode 5).
The Doctor (Siegel/Wexler) (played by Victor Raider-Wexler): The doctor who performed the surgery in "The Junior Mint", he was also the doctor who broke the news of Susan's death in "The Invitations" and who diagnosed George's atrophied condition in "The Summer of George". Also testified in "The Finale" about George's reaction to the news of Susan's death.
Peggy (played by Megan Cole) : appeared in season 8 "The Susie" as Elaine's coworker who mistakes Elaine for someone named Susie. She also appears in a season 9 episode "The Apology" and revealed to be a germophobe.
The Soup Nazi (played by Larry Thomas): Based on a real person (Al Yeganeh); a chef who often denied customers his delicious soup for the slightest misbehavior with the admonition, "NO soup for you!" The character's name, revealed in "The Finale", is Yev Kassem.
Nana (played by Billye Ree Wallace) is Jerry's grandmother and the mother of Helen Seinfeld and Uncle Leo. When her mind starts to mix up the present and the past, she reveals that Uncle Leo owes his sister, Jerry's mom, $50 from a racetrack bet their father won when they were kids.
Dolores (played by Susan Walters): Jerry's girlfriend; he doesn't know her name, only that it rhymes with a female body part (his best guess: "Mulva"). (The Junior Mint). Jerry reunites with her in "The Foundation".
Donald Sanger, aka The Bubble Boy (played by Jon Hayman): Jerry agrees to visit a bubble boy, who lives in a hermetically sealed bubble due to a compromised immune system. Jerry gets lost on the way, and George ends up meeting the bubble boy but finds he is a bratty spoiled kid; George and Donald get in a fight over a typographical error on a Trivial Pursuit card, when it says the Moops (rather than the Moors) invaded Spain. The fight results in the boy's bubble being popped.
Noreen (played by Kelly Coffield, In Living Color): A friend of Elaine's who dated Dan, the high talker. Elaine continuously destroyed Noreen's life until Kramer intervened and urged her to return to the military. She attempted to commit suicide, but Frank Costanza's cape-wearing lawyer (played by Larry David) stopped her.
Lloyd Braun (played first by Peter Keleghan, then by Matt McCoy): A childhood friend of George's. Estelle Costanza would badger George with "Why can't you be more like Lloyd Braun?" In "The Non-Fat Yogurt", Lloyd worked for David Dinkins until he passed along Elaine's suggestion that everyone in New York City wear name tags. Dinkins lost the race and Braun had a nervous breakdown. (The episode, which aired two days after the real mayoral election, was shot in two forms; had Dinkins been re-elected, Braun would've instead served in, and by taking Elaine's advice ruined, Rudy Giuliani's campaign.) After spending time in a mental institution, Lloyd helped Kramer gain historical status for a movie theater, in "The Gum". In "The Serenity Now," Braun worked for a short time for George's father, Frank Costanza, allegedly selling computers (although the phone line he was "using" wasn't connected). Larry David named the Lloyd Braun character after the real-life Lloyd Braun, who was David's lawyer and manager.
Babu Bhatt (played by Brian George): From Pakistan. Jerry seems to mess up his life at every turn, by giving bad business advice on his restaurant and by not passing on his immigration notice that is accidentally delivered to Jerry's mailbox. Babu thinks that Jerry is a "very, very bad man" (wagging his finger).
Barbara "Babs" Kramer (played by Sheree North): Cosmo Kramer's mother. She used to be a matron in the women's restroom at a restaurant, but was persuaded by Kramer to resign from that job and pursue an undefined venture with him. Although first mentioned in "The Nose Job," her first on-screen appearance is in "The Switch", where she also unintentionally reveals Kramer's first name to be Cosmo and has a sexual encounter with Newman. Babs was once addicted to alcohol and/or drugs claiming to have been "clean" for two years.
Bob Cobb (played by Mark Metcalf): A conductor who prefers to be called "Maestro" and has a villa in Tuscany. Cobb introduced Kramer and Frank Costanza to the trick of taking their pants off before sitting so the pants will "keep the crease". The character is named after the inventor of the Cobb Salad.
Poppie (played by Reni Santoni): Owner of an Italian restaurant who disapproves of abortion, tells traumatizing stories of his mother's death, is very strict on his idea of what pizza is, and developed stress-activated incontinence because of Elaine, which further causes him to stain Jerry's couch. The "Poppie couch" turns up in "The Doorman".
Marla Penny aka "The Virgin", played by Jane Leeves (Frasier): Professional closet organizer whom Jerry dates. She eventually loses her virginity to John F. Kennedy, Jr. Appears in "The Virgin", "The Contest", "The Pilot, Part 1" and "Part 2", "The Finale"
Izzy Mandelbaum (played by Lloyd Bridges): Fellow resident of Jerry's parents in Del Boca Vista in Florida; head of family-owned Magic Pan crepe restaurants. His favorite saying is "It's go time!" He is obsessed with his physical fitness. In "The English Patient" he throws his back out twice after being challenged by Jerry. Appears in "The Blood" and "The English Patient" (Season 9).
Scott Drake (played by Rick Overton): A mutual friend of the main characters, often referred to with the phrases "Love the Drake" or "Hate the Drake". Jerry, George, Elaine and Kramer give him and his fiancée a big screen TV as a wedding gift, only to find out soon after that they have broken up and his ex-fiance, the "Drakette", gave it away to charity. In "The Pilot, Part 2", the Drake and Drakette (who have gotten back together) are seen watching Jerry's pilot program on a small, handheld black and white television. In The Label Maker, he is engaged to marry The Drakette again, but they break up after he learns that the wedding is on the same day as the Super Bowl and tries to postpone it.
Leslie (played by Wendel Meldrum): Kramer's "low-talking" girlfriend, a clothing designer who designed the new puffy shirt featured in "The Puffy Shirt" episode. She also appeared in "The Finale" as a witness in the trial, but her testimony was not accepted because no one in the courtroom could hear her.
Joe Mayo (played by Pat Finn): Another mutual friend of the main characters, except Kramer. Hosts parties and assigns chores to the guests. Kramer later confesses he's never heard of him, and that to him, the name 'Joe Mayo' sounds made up. Joe Mayo is also a reference to a crew member of the series.
Alec Berg (played by Mark DeCarlo): Friend who gives ice hockey tickets to Jerry in "The Face Painter". Named after Alec Berg, one of the series' writers. Jerry thinks the name would sound particularly appealing when spoken by John Houseman. Jerry is apparently snubbed by Berg because Berg felt that he was due another "thank you" or two for the tickets.
Sue Ellen Mischke (played by Brenda Strong): Known as the "bra-less wonder", heiress to the Oh Henry! candy bar fortune, and nemesis of Elaine, whom she knew since they attended high school together in Maryland. She bids up the price of a set of golf clubs once owned by John F. Kennedy, which Elaine's boss J. Peterman had asked Elaine to buy at an auction, exceeding his limit. In "The Caddy", Elaine is so incensed that Sue Ellen doesn't wear a bra that she gives her a bra as a gift, which Sue Ellen then promptly wears as a top. This causes Kramer to crash George's car when he and Jerry see her walking in her bra down the street. The courtroom scene that follows is an allusion to the O. J. Simpson trial, ending with Jackie Chiles exclaiming that a bra has to be worn up against the skin, "like a glove." In "The Betrayal", Sue Ellen invites Elaine (accompanied by Jerry and George) to India for her wedding. Elaine and Sue Ellen briefly reconcile their animosity before it is revealed that Elaine once had a relationship with Sue Ellen's groom. She also appears in "The Bottle Deposit, Part 1" and "The Abstinence". Interestingly, there was a character named Sue Ellen Mischke, mentioned in the pilot episode of the sitcom Happy Days.
Ping (played by Ping Wu): Chinese food delivery boy, who sues Elaine after hitting a car while trying to avoid colliding with her as she is jaywalking. When asked how he felt after the accident Ping replied, "Head huwt, head weally huwt!" In "The Tape", when George calls a Chinese company to order hair growth cream, Ping acts as the interpreter.
Joe Temple: A family man who George watches Breakfast at Tiffany's with in the episode "The Couch". Joe dislikes George after he spills grape juice on his couch. Joe also appears in "The Diplomat's Club", where George tries to watch another film with him.
Remy Temple: Joe Temple's daughter. She is a great fan of Audrey Hepburn, and watched Breakfast at Tiffany's with her father and George in "The Couch". She appears again in "The Diplomat's Club" when George brings another Audrey Hepburn film, but her father tells her to get up to the apartment instantly before George came up.
Lindsay Enright: (played by Jessica Hecht) An ex-girlfriend of George's, was in a book club in "The Couch". They were supposed to read Breakfast at Tiffany's but George watched the film instead, and stated incorrect facts about the book. She then appears in "The Gymnast".
Jake Jarmel: (played by Marty Rackham) Author Elaine dated for a period. Dislikes using exclamation marks in "The Sniffing Accountant". Broke up with Elaine after she bought Jujyfruits immediately after hearing he was in a car accident ("The Opposite"). Bought his glasses in Malaysia so no one else would have a pair like them ("The Scofflaw"). He started a fight with Mr. Lippman when he noticed that Lippman had the same "unique" frames as himself. The actor who plays Jake Jarmel also appears as an LAPD officer in the episode "The Trip".
Mr. Kruger (played by Daniel von Bargen): President of Kruger Industrial Smoothing, for which George Costanza works during most of the ninth and final season. Kruger is noted for his total apathy towards his job and the success of his company. George's description of the company is "Kruger Industrial Smoothing: 'We don't care, and it shows'" ("The Strike"). George is often forced to push Kruger to do his work, to which Kruger usually responds, "I'm not too worried about it." He also attends the Festivus dinner. Kruger's company "botched the Statue of Liberty" job as they "couldn't get the green stuff off" and is infamous for losing money (when viewing the company financial reports Kruger nonchalantly exclaimed, "wow, we really took it on the chin last year"). Kruger appears in four episodes: "The Slicer", "The Strike", "The Burning", and "The Maid".
Sally Weaver, played by Kathy Griffin (Suddenly Susan, Kathy Griffin: My Life on the D-List): Susan Ross's roommate in college, originally from Memphis, Tennessee, she appears in "The Cartoon" and "The Doll" as an aspiring actress and comedienne. In "The Doll", she was indirectly responsible for ruining Jerry's bit for The Charles Grodin Show, not once but twice. In "The Cartoon" she becomes famous and even gets a cable special for her one-woman show, titled "Jerry Seinfeld is the Devil", which naturally becomes a favorite of Newman's. In "The Doll", it was revealed that Sally was an executive at Federal Express.
Mr. Morgan (played by Tom Wright) A coworker of George's at Yankee Stadium. He appears in four episodes, "The Pledge Drive", where George convinces Mr. Morgan that the Yankees should send a player to a PBS fundraiser after he sees George eating a candy bar with a knife and fork; "The Diplomat's Club", where he hints that George had a racial bias after George said that he looked like Sugar Ray Leonard; "the Mom and Pop Store", where George calls a meeting to convince the Yankees to have a "Jon Voight Day", and Mr. Morgan proposes they have no more meetings called by George; and "The Wink", where George causes a dispute with Mr. Morgan, his wife, and Mr. Steinbrenner by winking involuntarily, ultimately leading to Mr. Morgan's termination, and George being promoted to his position.
Wyck Thayer (played by Bruce Davison): Chairman of the Susan Ross Foundation, who assumes that George actually killed Susan. Appeared in the first two episodes of the eighth season, as well as "The Van Buren Boys" later in the same season. George consistently calls Wyck "Wink".
Franklin Delano Romanowski, aka "FDR", (played by Michael McShane): Another of Kramer's eccentric friends. In "The Betrayal", he uses his birthday wish against Kramer as the result of a grudge held after Kramer struck him in the back of the head with a snowball. The same actor also appears briefly in "The Wizard" as the hot dog vendor talking with George. Although his character's name is not revealed, he is presumably the same character because he was seen selling hot dogs in "The Betrayal" also. He is mentioned by Kramer in several episodes, usually in some outrageous anecdote.
Sal Bass (played by Tony Amendola): Kramer meets him at the health club and thinks he is Salman Rushdie. In a later episode, Sal Bass is shown watching Jerry's pilot program with Sidra. Out of the blue, Bass remarks, "You know, that Kim Novak had some really large breasts."
Bob and Ray/Cedric (played by Yul Vazquez and John Paragon): Hostile effeminate Latino duo that accost Cosmo Kramer in "The Soup Nazi", "The Sponge", and "The Puerto Rican Day". They are widely known as "street toughs". They steal Elaine's armoire that Kramer is guarding in "The Soup Nazi", verbally and physically attack him for not wearing an AIDS walk ribbon in "The Sponge", and attack him when he accidentally sets fire to a Puerto Rican flag. John Paragon's character is credited as "Ray" in "The Soup Nazi", but is addressed and credited as "Cedric" in "The Sponge".
Mabel Choate (played by Frances Bay): The woman at Schnitzer's deli who bought the infamous last marble rye, which Jerry went on to steal from her on the street in order to give to George to carry out one of his numerous idiotic schemes. She reappeared in a later episode at Del Boca Vista to cast the deciding vote in Morty's impeachment, when she recognized Jerry as the thief of her rye. She also appears in the final episode of the series as a witness testifying against Jerry, again bringing up the marble rye.
Ricky (played by Sam Lloyd): The man that takes Frank Constanza's TV Guide from Elaine in the subway and later turns it into a bouquet to declare his affection for her during "The Cigar Store Indian". He reappears in a later episode "The Pie" where it is revealed the reason mannequins looking like Elaine are appearing all over New York and Chicago is because he still thinks of her.
Allison (played by Kari Coleman): George's ex-girlfriend whom he claims is obsessed with him, proven by the fact that she threatened to kill herself if George broke up with her. Furthermore, in the end of the episode, "The Smelly Car", Allison, in an apparently lesbian-like manner, compliments the vest of George's other ex-girlfriend, Susan, with whom she is seen watching the pilot program in a later episode, "The Pilot".
Tia Van Camp (played by Jennifer Campbell): Blonde supermodel whom Jerry is seated next to on an airplane flight back to New York ("The Airport"). Jerry ends up getting a future date with Tia, who also appears in a subsequent episode ("The Pick"). Tia eventually dumps Jerry when she notices him in his car, appearing to pick his nose.
Sid: Professional car parker. George fills in for him briefly in "The Alternate Side" and fails miserably, directly causing Sid's nephew to lose his foot to amputation because George's incompetence caused several of Sid's regular customers to quit. This created a significant loss of income to Sid, thereby rendering him unable to finance his nephew's operation. Sid appears again in "The Parking Space".
Earl Haffler: Appeared in "The Diplomat's Club". He made bets with Kramer on which planes coming to the airport would arrive later than scheduled. Earl appears again in "The English Patient", where his deal with Kramer to buy "Cubans" falls through and he orders Cosmo out of his office.
Ramon: (played by Carlos Jacott): Annoying pool boy at Jerry's former health club who tried to become friends with Jerry, but Jerry did not want to be friends with Ramon because he did not need a fourth friend. Of course, Ramon thought it was because he cleaned pools for a living. He later becomes friends with Newman. He was originally fired from the health club for using too much chlorine but has his job back there again for unknown reasons. Some time later at the health club he is nearly killed when Jerry pulls him into the pool and Newman suddenly jumps on him whilst yelling "Ollie ollie oxen free!". During this incident, Jerry and Newman don't give him CPR and have their gym memberships terminated for failing to try to save Ramon's life ("The Pool Guy"). He also appears in the courtroom in "The Finale".
Mike Moffit: (played by Lee Arenberg): Calls Jerry a "phony" behind his back and gets into an argument with George over a parking space in front of Jerry's apartment ("The Parking Space)." He also appears as Kramer's bookie in "The Susie", where Jerry accidentally breaks his thumbs and traps him in the trunk of Jerry's car.
Rebecca DeMornay (not to be confused with the actress): (played by Sonya Eddy): A thrift store clerk who is in a constant state of agitation and is prone to violence. In another episode she works with the homeless. She once threatened to jump over the counter and punch George "in the brain". Appears in "The Bookstore" and "The Muffin Tops".
Lt. Bookman, played by Philip Baker Hall (Secret Honor): A library cop that Jerry has eluded since his 1971 checkout of Tropic of Cancer. His dedication to his job and coincidental surname are cause for Jerry's dismissive attitude towards him. He accuses Jerry of preventing other youngsters from experiencing the book's sought after adult-themed content or as Bookman refers, "pee-pees and wee-wees". His character is defined by his deadpan delivery (a parody of Sgt. Joe Friday in Dragnet) and tendency to dramatically flip his trench coat during interrogations. Appears in "The Library" and "The Finale, Part 2"
Matthew: (played by John Christian Graas): Son of the purveyor of the "fat-free" yogurt, Matthew is a 10-year-old boy who idolizes Jerry. He overhears Jerry swearing, and, following his idol's lead, refers to Jerry as a "funny fuck"("fuck" is censored). He ruins an audiocassette of Jerry's comedy, at which Jerry lets loose a torrent of obscenity. When the yogurt is revealed to have fat, Matthew cusses out Jerry again. Matthew first appears in "The Parking Space" in Season 3 and puts in his two cents over whether George has a parking space. Appears in The Non-Fat Yogurt and The Parking Space.
Joey (played by Todd Bosley): A 9 year old boy who lives in the same apartment building as Jerry, Kramer and Newman. Joey's mother asks Kramer to babysit him but due to his tight jeans, this results in Joey mistaking him for Frankenstein and running away. By his second appearance, they are friends and go to the same karate class, despite Kramer being many years older. Joey and his friends later beat up Kramer because he was able to beat them so easily in Karate. He appears in both Season 7's The Wait Out and Season 8's The Foundation.
Rachel Goldstein: (played by Melanie Smith): Jerry's most dated girlfriend in the series, having appeared in four episodes (including a two-part episode). In The Raincoats, she and Jerry make out while watching Schindler's List and are seen by Newman, who informs Jerry's and Rachel's parents of the incident. As a result, her father tells Jerry she won't be seeing him again but they are still together later in the series. In "The Hamptons", Rachel accidentally walks in on George naked while he is a victim of "shrinkage", having just gotten out of the pool. She tells George's girlfriend, who immediately returns home as a result. In "The Opposite", she breaks up with Jerry, who quickly says he'll find somebody else as things always even out for him.
Tina Robbins: (played by Siobhan Fallon Hogan (Men In Black)): A "waitress/actress" (although she considers herself an "actress/waitress") who is Elaine's roommate in her original apartment, later moving out and sub-letting it to her. She is introduced in "The Deal" and dates Kramer in "The Truth", much to the dismay of Elaine, who complains about the loud tribal music and sexual noises in her apartment. She makes a brief appearance in "The Opposite", kicking Elaine out of her apartment for, among other things, buzzing up a jewel thief and using Canadian quarters in the washing machine.
Deena: (played by Mary Jo Keenan of Nurses): A childhood friend of George who thinks that he is mentally unstable after she repeatedly catches him in bizarre situations. First, in "The Gum", she notices striking similarities between George's behavior and that of her mentally unstable father (affectionately known by all as 'Pop'), that being "nervousness, irritability, and paranoia". Her suspicions are heightened when she sees him walking down the street in a King Henry VIII costume telling people he just left the 'institution'. Then, in "The Doll" she catches him in the coffee shop, alone and screaming at a doll that looks like his mother. Finally, in "The Bottle Deposit" she is visiting her father at the mental asylum when she runs into a hysterical George, who was mistakenly sent there by Mr. Steinbrenner. She ignores his pleas to help him escape, believing that he is finally getting the help he needs.
Rabbi Glickman: (played by Bruce Mahler): A rabbi who befriends Elaine (and actually makes a clumsy play for her at one point) and is a terrible secret keeper. He appears in "The Postponement", "The Serenity Now", and "The Finale".
Rusty: (played by Jon Gries): Homeless man who falsely identifies Kramer in a police lineup and is hired by Kramer and Newman as labor for their short-lived rickshaw venture. During his trial run, Rusty stole the rickshaw. He appears in "The Beard" and "The Bookstore".
Jiffy Park Guy/Jiffy Dump Guy: (played by Chaim Girafi): An attendant at Jiffy Park who may or may not be utilizing George's car, along with other cars parked on the lot, as a den of iniquity for prostitutes to conduct their business in the episode "The Wig Master". His second appearance was in "The Muffin Tops", where he portrayed the late-night operator of sister-company Jiffy Dump, who steadfastly refuses to accept trash bags of discarded muffin stumps. (Jiffy Dump Guy: "Where are the muffin tops?" Kramer: "This is a garbage dump. Just let me dump it." Jiffy Dump Guy: "Can't do it." Kramer: "Is this a joke?" Jiffy Dump Guy: "That's what I'd like to know about it.") In both episodes, he suggests that George and Kramer resolve their issues with "Consumer Affairs".