The Waitress is a woman openly stalked by Charlie Kelly, despite numerous restraining orders. ("The D.E.N.N.I.S. System") She went to high school with the Gang, and used to work at a local coffee shop frequented by Charlie. She attends the high-school reunion with the Gang, where her name tag is missing (further implying her status as 'easily forgettable', a theme in that episode), preventing her name from being revealed. Many fans assumed her name was Nikki Potnick when Frank showed up with a stolen tag bearing that name. However, Glenn Howerton specified on Twitter that this is not the case.
The Waitress has often worked a number of side jobs to make extra money: first as a manager of a corporate pub ("The Gang Sells Out"), later as a booth manager at a local fair and most recently delivering food. She lives in an apartment in Philadelphia.
The Waitress is a recurring character, appearing in every season. She is portrayed by Mary Elizabeth Ellis.
The Waitress is an on-and-off again alcoholic. ("The Gang Gives Back") ("Who Pooped the Bed?") ("The Waitress Is Getting Married") She has been a member of Alcoholics Anonymous in the past("The Gang Gives Back"), although she has relapsed at least twice. When drunk, she is rude and belligerent. ("Who Pooped the Bed?") ("The High School Reunion")
The Waitress is frustrated by Charlie Kelly's obsessive stalking. She has no interest in Charlie, but has harbored an unrequited crush on Dennis. Dennis has played with her feelings so many times that she now has a love/hate relationship with him, depending on whether or not he is expressing interest in her. She slept with Frank Reynolds in ("Mac Bangs Dennis' Mom"). She also has a desire for revenge on Dennis, which has resulted in her trying to win Paddy's Pub in a dance contest. ("The Gang Dances Their Asses Off")
Charlie goes to great lengths to woo The Waitress, even going so far to express his affections and intentions with a musical production.
The Waitress has low self-esteem, which has allowed various people to manipulate her in humiliating ways:
- The Waitress agreed to have sex with Charlie in exchange for $250 but simply went on a date with him instead. Mac and Dennis fail to get a refund after they find out. ("Charlie Has Cancer")
- The Waitress slept with Frank to get back at Dennis. ("Mac Bangs Dennis' Mom")
- Dee manipulates The Waitress into giving her a job at the corporate pub, because then Dee might say nice things about her to Dennis. ("The Gang Sells Out")
- Dee convinced her to grind a homeless guy to make Dennis jealous. In actuality Dee was trying make Charlie jealous so that he would lose the dance contest. ("The Gang Dances Their Asses Off")
- Brad Fisher proposed to her after a very short period of time, and she accepted; later it emerged that he was just getting revenge for how she treated him in high school. ("The Waitress Is Getting Married")
- While drunk, she agreed to have sex with the first person who talked to her. This person turned out to be Schmitty. ("The High School Reunion, Part 2: The Gang's Revenge")
The Waitress appears to be concerned for her safety. She warned Charlie that she carried Mace in "The Nightman Cometh". She sprayed a Mace-like can on Dee and Dennis when they followed her late at night. ("Mac Is a Serial Killer")
The Waitress went to high school with The Gang but none of them (except Charlie) seem to remember her. She sat next to Dee in Trig. ("The Waitress Is Getting Married") In an earlier episode The Waitress asks Dee "if she went to high school?" when Dee tricks her into filling out a job application for her (In the syndication run of the episode the line is changed saying she doesn't know Dee's address). ("The Gang Sells Out")
As Charlie has coffee with Mac and Dennis, they talk about Terrell's plans for recruiting people to the bar. They repeat his assurances about filling the bar, quoting "there will be niggers hanging from rafters." The Waitress overhears and refers to Charlie as Hitler. He later takes a black girl, Janell, on a date to the coffee shop to prove he is not racist, but The Waitress reveals his plan to Janell. ("The Gang Gets Racist")
While Charlie is spending the day with his supposed son Tommy, Charlie bumps into The Waitress at a toy store. She tells him that she is a member of the Big Sisters of America program, and he lies, telling her that he and Tommy are also in the program in order to secure a date with her at a program picnic. Later, after Tommy was sneaking drinks from the bar, Waitress discovers Charlie yelling at a drunk Tommy in the alley. ("Charlie Wants an Abortion")
After seeing her wear a Livestrong bracelet, Charlie schemes up a strategy to get her to date him starting with telling Dennis he has cancer. Dennis works with Mac to get Charlie laid and decides to guilt The Waitress into banging him. However, when Dennis tells her Charlie is ill, she responds by condoling Dennis who takes advantage and sleeps with her. Mac then pays her $250 to sleep with Charlie, but instead she takes him out for the day and makes him buy her jewelry and clothes. ("Charlie Has Cancer")
Charlie runs into The Waitress at an Alcoholics Anonymous meeting, which he must attend as part of his sentence for setting fire to Ari Frankel's property. The Waitress agrees to be his sponsor, but soon Charlie abuses her kindness by using this as an excuse to constantly go to her apartment. She, in turn, uses him to get her close to Dennis, who is coaching a kids' basketball team as part of his sentence for the fire. When Dennis uses the fact she is Charlie's sponsor as his excuse to turn her down when she asks him out on a date, she stops being Charlie's sponsor, which causes him to start drinking again. ("The Gang Gives Back")
Dennis attempts to get out of Charlie Work by telling Charlie he will bang The Waitress unless Charlie agrees to do all the Charlie Work for him. Charlie's scheme to get back at Dennis by encouraging Mac to bang Dennis' mom leads to a series of complications that eventually leads The Waitress to bang Frank to get back at Dennis after she spots him trying to bang both Mac and Charlie's moms to get back at them. ("Mac Bangs Dennis' Mom")
The Waitress relates that a Starbucks has moved in across the street, and is taking away all the business from her coffee shop. ("The Gang Sells Out") She is forced to supplement her job at the coffee shop by working at a corporate pub as the manager. She gets fired from the pub after being manipulated into hiring Charlie, Dee and Dennis, who completely ignore her directions and continue to behave as they do at Paddy's.
As part of their effort to get inside the mind of a serial killer, Dennis and Dee decide to start stalking The Waitress, as though they were serial killers stalking their prey. However, The Waitress detects them (largely due to the squeaky shoes that are part of Dee's "killer clown" costume) and she blasts both of them in the face with a large can of pepper spray. ("Mac Is a Serial Killer")
The Waitress promises to sleep with Mac so she can find and destroy the sex tape Dennis made of him banging The waitress. She then tells Mac that she'll only have sex with him if they do it at Charlie's apartment; this is so she can find and destroy yet another sex tape Frank has made of him banging her, but The Waitress finds that Charlie has already destroyed the tape. ("Mac's Banging the Waitress")
Charlie creates the musical "The Nightman Cometh" to woo The Waitress into accepting his marriage proposal. She only agrees to attend because Charlie promises to never bother her again if she shows up. She refuses Charlie's proposal, and Charlie renegs on his promise. ("The Nightman Cometh")
The Waitress gets engaged to her high school ex-boyfriend Brad Fisher. Dee who also dated Brad in high school attempts to break it up. Brad reveals that he was leading both women on for dumping him in high school because of his acne. ("The Waitress Is Getting Married")
The Waitress has a new side job working at a carnival. ("The D.E.N.N.I.S. System")
The Waitress gets dirty mop water dumped on her during Dennis and Dee's podcast. ("Mac's Big Break")
Charlie hallucinates that The Waitress was at the Halloween party. ("Who Got Dee Pregnant?")
When The Gang visits the Jersey Shore, Charlie breaks off to explore the beach himself. While playing in the ocean, he finds The Waitress walking along the beach. She allows him to hang out with her, and the two spend the night talking, laughing, and enjoying the beach. When she wakes up in the morning, she is freaked out for living one of her worst nightmares. She tells Charlie she was tripping on Ecstasy the night before. ("The Gang Goes to the Jersey Shore")
The Waitress attends her high school reunion completely drunk. Nobody remembers her and she does not have a nametag. Nobody wants to talk to her, and she sits alone at a table by herself. ("The High School Reunion") She continues to get drunk and when the reunion ends she offers to bang the next man who talks to her. Before Charlie can say a word, Schmitty arrives and talks to her and takes her home. ("The High School Reunion, Part 2: The Gang's Revenge")
The Waitress demands that Charlie stop stalking her, and, unexpectedly, Charlie agrees, and soon begins dating Ruby Taft. It turns out that Charlie has not merely been stalking her: he has been performing a whole series of tasks to help her, such as chasing off people who might steal her bike, putting vitamins in her shampoo, and testing her food for poison. Without Charlie helping her out, her life starts to fall apart, and she appeals to Dennis to help her. Dennis sends Frank out with the list Charlie keeps of what he does for The Waitress, which Frank, not surprisingly, has trouble reading. Frank mixes up some of the tasks, such as thinking that Charlie puts rat poison in her shampoo, causing her hair to fall out. He hits The Waitress with his car as he follows her around keeping her bike from being stolen. In the end, it turns out that Charlie was using Ruby to make The Waitress jealous. The Waitress asks Charlie to go back to whatever he was doing for her, and even agrees to reduce the distance he has to stay away from her from 100 to 50 feet. ("Charlie and Dee Find Love")
In his (animated) fantasy of how he handles the convenience store robbery The Gang has found itself stuck in the middle of, Charlie saves The Waitress from being shot when she comes into the store by throwing Dee in front of the bullet. The Waitress is won over by his act of heroism, and she moves into Charlie's apartment with him. She is horrified by the rats she sees there, but is ultimately charmed when they turn out to be helpful friends, making her a lovely wedding dress, making them a romantic dinner, and ultimately building them a house. They have a large family together (obtained in a trip to the Baby Store), and live a happy life, growing old together, until The Waitress finally dies. Charlie is alone in his grief for a while, but decides to get out of it by filling the house with balloons and letting it float away. ("The Gang Saves the Day")
When the "intelligence drug" that Charlie is taking makes him start to separate himself from the rest of The Gang, Frank tries to get him back by paying The Waitress to go on a date with him. However, Charlie, who has become far more intelligent since starting to take the experimental drug (or at least thinks he's become more intelligent), finds The Waitress to be vapid and ends the date. ("Flowers for Charlie")
Dennis, reeling from his extremely low rating on a website where women rate men they have dated, takes The Waitress out to dinner at Guigino's. He tells The Waitress that he has realized that he has treated women -- including, of course, The Waitress -- poorly over the years. He offers The Waitress a "promise ring", with which he promises to "treat [her] nice", in return for her giving him a good rating on the rating website. However, The Waitress doesn't have Internet access (or, as she says, she doesn't "have the online") and even has an ancient phone that is actually just a phone. After he hears this, Dennis storms out of the restaurant in disgust. ("The Gang Group Dates")
As part of Level Three of a game of Chardee MacDennis, Charlie has to endure one minute of intense public humiliation from The Waitress without crying. He loses. ("Chardee MacDennis 2: Electric Boogaloo")
The Waitress comes to Charlie and Frank's apartment, lured there by Mac who told her the apartment was available. She tells them that she has been going through very rough times and is living in a women's shelter. When she finds out Mac was lying about Charlie not living there anymore, she gets angry and says she'd rather live on the streets than live with Charlie. Charlie then tries to toss her out the window, because he believes it's a "time portal" since Frank has believed that the year is 2006 since he fell out the window (though this is due to a head injury, not because of actual time travel.) Mac rescues her and she escapes. ("Frank Falls Out the Window")
- Season One: The Gang Gets Racist, Charlie Wants An Abortion, Charlie Has Cancer
- Season Two: Mac Bangs Dennis' Mom, The Gang Gives Back
- Season Three: The Gang Finds a Dumpster Baby, The Gang Sells Out, Mac Is a Serial Killer, The Gang Dances Their Asses Off
- Season Four: Mac's Banging the Waitress, Who Pooped the Bed?, The Nightman Cometh
- Season Five: The Waitress Is Getting Married, The D.E.N.N.I.S. System
- Season Six: Mac's Big Break, Who Got Dee Pregnant?
- Season Seven: The Gang Goes to the Jersey Shore, The High School Reunion, The High School Reunion, Part 2: The Gang's Revenge
- Season Eight: Charlie and Dee Find Love
- Season Nine: The Gang Saves The Day, Flowers For Charlie
- Season Ten: The Gang Group Dates
- Season Eleven: Chardee MacDennis 2: Electric Boogaloo, Frank Falls Out the Window
- As a recurring joke, none of the characters (with the possible exception of Charlie) seem to know her real name and she is simply referred to as "The Waitress". When she starts to call Dennis after Charlie stops stalking her (temporarily), she introduces herself by her real name, which he does not recognize at all. ("Charlie and Dee Find Love")
- Her real name has not been revealed, other than two clues:
- Charlie lists The Waitress as his emergency contact (which would suggest that he knows her name, but then again - who knows?). ("The Nightman Cometh")
- The sex tape that Dennis made with The Waitress is filed simply as "Waitress (Coffee Shop)". And she only got one star. ("Mac's Banging the Waitress")
- She doesn't have any friends. ("Who Pooped the Bed?")
- She has a cat named Frederick, but he died three weeks before. ("Who Pooped the Bed?")
- Because of her alcohol problem, The Waitress gets her gums to bleed. (The Gang's Dating Profiles)
- Actress Mary Elizabeth Ellis in real life is Charlie Day's wife (since 2006). Also, in 2004 they did cameos on the popular mockumentary comedy series "Reno 911!" (s02e07): they played a couple of incestuous twin brother and sister, more in the McPoyles manner.
- The Waitress might be stalking Dennis Reynolds - for example, she somehow got Dennis' new cell phone number after he changed it. ("Charlie and Dee Find Love")
- The Waitress has appeared in more episodes than any other recurring character: 23.
- Along with Artemis and Charlie's mom, The Waitress is the only other recurring character who has appeared in the first six seasons of the show.
- The Waitress is the only recurring character to appear in all eleven seasons of the show.
- There was fan speculation that Nikki Potnick was the real name of The Waitress. In the 7th season episode "The High School Reunion" Frank steals Nikki Potnick's nametag to get into the reunion, and later The Waitress shows up without a nametag and says someone stole hers. Glenn Howerton tweeted in response that, "Sorry, but the Waitress' name is not Nikki Potnick. If u wanna know who N.Potnick is, re-watch S.1 Underage Drinking. First 10 mins." 
- The tweet is a reference to a story Charlie tells in which the gang, while drunk back in highschool, drove Nikki Potnick's car into a tree, while Dee was puking in back seat
- In a shape of joke: The Waitress' real name.
- Charlie and the Waitress - Details on Charlie's stalking of The Waitress.
- Dennis and the Waitress - Details on The Waitress' off and on crush on Dennis.
- Dee and the Waitress - Details on their shallow friendship.
- Dennis Reynolds ("Charlie Has Cancer")
- Frank Reynolds ("Mac Bangs Dennis' Mom")
- "Some random dude" (but not Charlie) ("Who Pooped the Bed?")
- Brad Fisher ("The Waitress is Getting Married")
- Schmitty ("The High School Reunion, Part 2: The Gang's Revenge")