In the very first episode, the first conversation was between George and Jerry about a button. In the very last episode, when they were sitting in jail, the last conversation they had was the same thing about the button.
As Kramer became more popular, his entrance applause grew so prolonged that the cast complained it was ruining the pacing of their scenes. Directors subsequently asked the audience not to applaud so much when Kramer entered.
Larry David famously instituted a policy of "no hugging, no learning", meaning that the show must avoid sentimentality and moral lessons, and the characters must never learn or grow from their wrongdoings.
When the final episode aired on May 14, 1998, the TV Land network honored the occasion by airing no programming in the show's timeslot. Instead the network just showed a still photo of a closed office door.
The costume department always gave Michael Richards clothes that were one size too large, to make Kramer appear laid-back and loose. Conversely, they gave Jason Alexander clothes that were one size too small, to make George look uncool.
The character of Cosmo Kramer is based on Kenny Kramer, a man who worked across the hall from co-creator Larry David. In a self-confessed move to cash-in on the sitcom's popularity, Kenny Kramer formed the "Kramer Reality Tour", an officially-recognized New York City tour which visits the real-life locations often featured in the sitcom. In the 1997 season of "Seinfeld", Cosmo Kramer's memoirs are published by J. Peterman as his own. Wanting to make the most of the situation, Cosmo Kramer starts a "Peterman Reality Tour", offering a tour of the real-life locations featured in the memoirs.
Larry David, co-creator and executive producer, appears several times throughout the series. He is the voice of George M. Steinbrenner III, The Man In The Cape (Frank's divorce lawyer) and the owner of a newsstand (in the "Chinese Gum" episode he sells George gum). He was also one of the last voices heard on the show, as the prisoner who yells "I'm gonna cut you!" at the very end of the final episode.
In the episode where Elaine dates a man named Joel Rifkin, she tries to have him change his name, since Joel Rifkin is also the name of a man involved in a notorious New York City murder case. One of the initial suggestions for a new name was O.J. This episode was shot in 1993, a year before O.J. Simpson was accused of murdering his ex-wife Nicole Brown Simpson and Ron Goldman.
The apartment used for exterior shots of 129 West 81st Street, New York, New York, is not actually in New York at all, but is 757 S. New Hampshire Avenue, Los Angeles, California. There's a Taco Bell directly across from it.
Before the show was set to air, Jerry Seinfeld asked Jason Alexander what he thought their chances for success were. Alexander said he thought they "didn't have a chance." When asked why, Alexander responded, "Because the audience for this show is me, and I don't watch TV."
Every episode of the series - except "Male Unbonding" - begins with "The..." and names something from the episode. This was done because Jerry Seinfeld didn't want the writers wasting time creating witty titles.
In one of the episodes, Jerry is walking down the street with one of his buddies, and in the background, there's a building with a sign on it that reads "Kal's Signs". Jerry Seinfeld's real life dad's name is Kal, and he really made signs for a living.
Many plots of the early episodes were completely based on the episode writer's real life troubles, including "The Chinese Restaurant", "The Jacket", "The Robbery", "The Cafe", "The Nose Job", and many others.
Julia Louis-Dreyfus was pregnant while shooting part of this series. Her pregnancy was disguised with her carrying props to hide her changing body. This was parodied on The Nanny (1993) when the very-pregnant Lauren Lane mentioned them hiding Elaine "behind all these huge props" while standing in front of a poster with "Baby" on it.
An episode titled "The Bet" in which Elaine buys a gun from Kramer's friend was written for season 2. It was not filmed because the content was deemed unacceptable and was hastily replaced by the episode "The Phone Message".
Jason Alexander originally based his portrayal of George on Woody Allen, which is why he wore glasses. When he realized that George was actually based on Larry David, he began basing his performance on David's mannerisms.
ABC Entertainment executive Lloyd Braun lent his name to a character appearing in three episodes, "The Non-Fat Yogurt", "The Gum", and "The Serenity Now", and is a neighbor and nemesis of George Costanza.
In the episode in which Kramer options his coffee table book for a movie and moves to Florida, several newspaper headlines are featured as he runs for condo council president. In smaller print on these pages, other headlines read, "Larry David Gets Hole in One" "Larry David Injures Elbow", and "Larry David Never To Play Golf Again".
Though Larry David played George Steinbrenner, the actual George M. Steinbrenner III was filmed playing himself for use in an episode. However, the scene was never shown on the series. Steinbrenner did appear with Jason Alexander (in the part of George) in a 1996 promotional spot for MLB All-Star Game balloting.
The restaurant exterior belongs to Tom's Restaurant, which is the same restaurant that was immortalized in the Suzanne Vega song "Tom's Diner." It is near the Columbia University campus in Manhattan at West 112th Street and Broadway.
While they are waiting in the Chinese restaurant, Jerry lists the many people that will be getting phone calls as a result of him being seen there. One of the included people was his sister. His sister has never appeared on the show, nor is she ever referenced again.
During the original airing of the finale, MTV aired original cartoons that were specially timed to fit into the finale's commercial breaks, so that viewers could freely watch both of them and not worry about missing anything.
Michael Costanza, Jerry Seinfeld's friend whom George is named after, filed a $100-million lawsuit against Seinfeld, Larry David and NBC, claiming invasion of privacy and defamation of character. Costanza claimed damages due to the show's alleged use of his likeness. The case was dismissed.
Jerry, George, and Kramer each had alter-egos that they used on occasion. Jerry's was Kel Varnsen, George's was Art Vandelay, and Kramer alternated between Dr. Martin Van Nostrand and H.E. Pennypacker.
The original script was called "Stand Up". It was to be a 90-minute mockumentary about how a stand-up comedian writes his jokes based on his everyday life. It was to air in place of Saturday Night Live (1975) for one night. NBC liked the script so much that they decided to develop it into a pilot instead.
In the final episode of the series, the trial pays homage to Inherit the Wind (1960). Particularly, the scene where the attorney discusses how many important people will descend upon their little town, because the case is so high profile.
Lee Garlington was originally supposed to be a member of the cast, as Claire, the coffee shop waitress who gave Jerry and George friendly advice. She appeared in the pilot episode. But when the show was picked up, her character was dropped.
Throughout the run of the series, Kramer rarely says "Yes". Nearly all of his positive responses are slang variations ("Yup", "Yeah!", "Giddyup" etc). Two episodes where he does actually say "Yes" are "The Puffy Shirt" and "The English Patient".
Kramer's wardrobe of mostly 1960s and 1970s clothing was not intended to make him into retro fashions, so much as to suggest that he hadn't bought clothes in several years. The pants in particular were always about an inch too short in order to stress this. In later seasons, appropriate clothing became increasingly difficult for producers to find, due to the combination of it getting older and older as well as the extreme popularity of Kramer as a character, forcing them to have tailors personally make Kramer's clothing out of retro fabrics. Often, they would create numerous back-up copies of the clothing in case it was damaged during the physical comedy.
As Larry David states on the DVD, the character of Elaine's father, the gruff war vet/author Alton Benes, was based on the late writer Richard Yates who was the father of his former girlfriend Monica Yates and author of the novel "Revolutionary Road"
Bob Balaban played an NBC network executive who approved a sitcom pilot to be called "Jerry". Balaban was chosen because of his resemblance to NBC executive Warren Littlefield, the man who allowed Jerry Seinfeld and Larry David to produce the "Seinfeld" pilot. Balaban also played Littlefield himself in the HBO movie The Late Shift (1996).
At Jerry Seinfeld's high school, Massapequa HS on Long Island, there was a teacher named Mr. Bevilaqua - he was the wrestling coach there. In one of the episodes Jerry had a race that was officiated by Mr. Bevilaqua.
In the series finale, Kramer suggests that he, George, Elaine, and Seinfeld do a musical such as "Bye, Bye, Birdie" or "My Fair Lady". Jason Alexander, who plays George, did in fact star in Bye Bye Birdie (1995) as Albert Peterson.
One of only three series in American history to rank #1 in the ratings for its entire final network season. The other two were I Love Lucy (1951) (in 1956-57) and The Andy Griffith Show (1960) (in 1967-68).
Newman was originally written as the African-American son of Jerry's landlord. William Thomas Jr. was cast and a scene featuring him was filmed but it was deleted. Tim Russ also auditioned for the role.
In addition to Jerry having a sister who is only mentioned once (in "The Chinese Restaurant"), George has a brother who is mentioned only twice in the series: "The Suicide" (his brother impregnated a woman named Pauline) and "The Parking Space" (George's father, mother and brother never pay for parking). Elaine has a sister, Gail, who she visits in St. Louis, and who she calls after she sends Gail's son her exposed nipple Christmas card. Elaine also mentions a brother-in-law (presumably Gail's husband) in "The Phone Message" (he blurted out secret business information on an answering machine).
Jerry is the only character to appear in every episode. Elaine does not appear in "The Seinfeld Chronicles" and "The Trip (Parts 1 and 2)", Kramer does not appear in "The Chinese Restaurant" and "The Pen", and George does not appear in "The Pen".
Elaine is loosely based on Carol Leifer, a friend of Jerry Seinfeld's whom he also used to date. She is also based on model Susan McNabb, who was Seinfeld's long-time girlfriend, and Monica Yates, whom Larry David dated.
In the very first show, Kramer's last name was Kessler. Jerry is heard saying Kessler exactly the same way as he does Kramer. This was because Kenny Kramer would not allow his name to be used on the show unless he was allowed to play Kramer. Eventually Kenny Kramer's list of demands were met, and the name Kramer was used.
Since her appearance on the show, the actress who played Jerry's pea-picking girlfriend (the one who insisted on eating her peas one at a time) is on record as saying that she now eats her peas with a spoon.