The titular American Housewife, and the second-fattest housewife in Westport. Forced to move to Westport because it has a public school with one of the best special needs programs in the country, she spends the series valiantly attempting to prevent her family from becoming corrupted by the materialism, vanity, and greed of the people who live there.
- Break the Haughty: Katie makes it her mission in life to take smug people down by a few pegs and, living in Westport, she is spoiled for choice when it comes to targets.
- Freudian Trio: Katie is The Kirk, forced to choose between Doris and Angela and their (usually contrasting) advice. She'll generally choose to listen to neither of them, ironically enough, when they're actually in agreement about something.
- Happily Married: Katie adores Greg, despite their many differences, and can always count on him to support her.
- Harmful to Minors: She's very lenient towards Anna-Kat, allowing her youngest to watch films with mature themes, to Greg's chagrin.
- How the Mighty Have Fallen: She sees living in Westport as this, saying she used to be quite popular back home but is an outsider here.
- Mama Bear: She's not afraid to take you to the ground, as Oliver's ballet teacher learned when she relentlessly picked on Oliver, assuming he was yet another spoiled Westport brat.
- Parental Substitute: Finds she's this to Cooper (Oliver's snobby friend) in Season 2. She can't stand him, but he really takes to her since his own parents are never around.
- Sitcom Arch-Nemesis: Katie is known for her large number of feuds with various people. The two biggest and oldest thorns in her side are Tara Summers and Chloe Brown Mueller.
Greg is a college history professor who met and fell in love with Katie when she was a student taking a course he was a TA for. Although the two are polar opposites - he is lean, well-read, polite, considerate, and mild-mannered - they are very fond of each other and have each other's backs through the ordeal of raising three difficult children in their crazy town.
- Beware the Nice Ones: Greg is much more easygoing than Katie, but push him far enough and he will make you regret it.
- Clueless Chick Magnet: He has no idea, but a lot of the women in Westport are attracted to him because of how nice he is and are hoping Katie dies relatively young so they can have a chance at wooing him.
- Endearingly Dorky: Greg is endearingly awkward and has certain character tics that Katie finds amusing.
- Epic Fail: In "Boo-Who?", he attempts to tell off Chloe Brown Mueller for making Katie feel bad. However, in addition to being nervous, he was in a Frankenstein's monster costume at the time, so he was pretty tired and sweaty by the time he got to Chloe's store. Some of the costume's make-up got in his eyes, he tripped, and caused a chain of accidents that destroyed the store merchandise. Unsurprisingly, Katie is nonetheless thrilled by that.
- Friend to All Living Things: Greg bought a special grill to roast a pig, but he just didn't have the heart to kill and cook the little guy.
- Happily Married: Although Katie pushes him around sometimes, it's clear she does love him deeply and the feeling is entirely mutual.
- Henpecked Husband: So much so that "The Pig Whisperer" sees everyone acknowledge that he always caves in to Katie, and he is determined to stand his ground for once.
- Nice Guy: Greg's kindness and attentiveness as a husband and father have garnered the attention of more than a few Westport women. Apparently Doris gets first crack at him in the event Katie dies young.
- "Well Done, Son!" Guy: "Family Secrets" shows him quite eager to please his parents, but he desperately wants the approval of his father, Thomas. It gets progressively deconstructed, as Thomas continually proves cold to Greg's overtures. Then it's revealed that Thomas had an affair in England and has had a second son for 20 years, so Greg finally blows up at him.Greg: My whole life, I've looked up to you. In my eyes, you couldn't do anything wrong. In your eyes, I couldn't do anything right! Well, it turns out I did everything right!
- In a rare example of an unhappy ending for this show, two years later when he finally meets his half-brother in person it's noted that Greg has not spoken with his parents ever since.
The oldest child of the Ottos, whose arrival was unexpected. Beautiful and athletic, Taylor is substantially the dumbest person in her family, easily outwitted by both her parents and her younger siblings. Katie's eternal fear is that she will be corrupted by her wealthy friends (and later her wealthy boyfriend) to prefer a life as arm candy rather than try to make something of herself.
- Brainless Beauty: A pretty girl, no question, but she ain't the sharpest tool in the shed.
- Bratty Teenage Daughter: Realistically portrayed. She's reached an age where she wants much more independence but her parents are reluctant to grant it so they clash. Katie even spends an entire episode wondering what happened to the sweet little girl Taylor used to be and decides to infect her own daughter with head lice to force mother-daughter bonding time.
- The Ditz: There's no way of getting around it: Taylor's really dumb.
- Dumb Blonde: Subverted - she's a natural brunette and began the series as one, and wasn't any smarter then.
- Everyone Loves Blondes: Dyes her hair blonde in one episode without Katie's permission.
- Hidden Depths: In Season 1, she befriends Viv not because of the snobbish lifestyle, but out of sympathy. Viv's husband is never around and the stepchildren revile her.
- Last Het Romance: Taylor is this to her first boyfriend, Eyo. After they break up, he starts dating Bruce Westfield, the (male) co-captain of the water polo team.
- Surprise Pregnancy: Katie and Greg hadn't intended on having their first child so soon after they were married, but Taylor had other ideas.
- What the Hell, Hero?: After she ditches her one true friend in Westport to hang out with popular girls, Greg gives her an angry dressing down, saying that her actions showed a fault in her character.
The Ottos' middle child and their only son. Obsessed with money, he often schemes to get rich quick, and comes up with some pretty devious ways to do so. As the series begins, Katie laments that they have screwed up completely with Oliver, but over the course of the series he discovers (much to his own shame and disappointment) that he does indeed have a conscience, one of the many things he blames his parents for burdening him with.
- Alliterative Name: Oliver Otto. Played by an actor with one as well: Daniel DiMaggio.
- Ambiguously Gay: The subject of the first-season episode "The Otto Motto", where Katie discovers an "attainment board" attached to the inside of Oliver's closet door, with lots of pictures of shirtless models and athletes (and his best friend, Cooper Bradford), leading her to assume he's gay. (Angela, a lesbian, remarks that his unpleasant personality could be due to the emotional toll of being an Armored Closet Gay.) When Katie and Greg discover he's enrolled in ballet classes they're convinced, but it turns out Oliver's taking ballet strictly to get into Harvard (though he does come to enjoy it) and the "attainment board" is full of pictures of people Oliver wants to be like. This subject is revisited several times in later seasons, with the Running Gag of Katie hoping Oliver is gay so that they can take a mother-son gay cruise together.
- Ballet Episode: Takes up ballet in Season 1 purely as a strategic move to earn a scholarship to Harvard. Actually enjoys doing it, however, and, as of Season 2, is attending more advanced classes in Norwalk. Unfortunately he has to stop doing ballet at the beginning of Season 4 due to a Career-Ending Injury, forcing him to find other extracurriculars.
- Break the Cutie: Oliver gets hit with a surprising amount of this throughout the show's run. All three of his major love interests dump him (Alice by two-timing him and then staying away after Anna-Kat threatens her, Gina by refusing to pass up the opportunity to attend an elite ballet school, and Brie by breaking up with him in solidarity with her friend dumping Cooper). Spencer Blitz, his mentor, abruptly passes on. He is injured, putting a premature end to his ballet career (and his planned ticket into Harvard). It even looks like his best friend Cooper might leave him, though ultimately he does not.
- Character Development: Oliver goes through more of this than any other character on the show. His (grudging) evolution into a good person is so complete that Katie, feeling genuine pride in her son's compassion, eventually comments that "it's like your soul is going through puberty".
- A Date with Rosie Palms: The other characters, particularly his mother, often imply that he masturbates frequently, although he always denies it and nobody ever actually claims to have caught him in the act.
- Expy: Early Oliver is very reminiscent of Alex P. Keaton.
- Heel Realization: In Season 2, he seeks to befriend Spencer Blitz, a disgraced but wealthy former investor, in the hopes of getting into his will. "Family Secrets" shows that it's working, but hearing Spencer refer to him as like family causes Oliver to feel guilty about what he's been doing.
- Heterosexual Life-Partners: With Cooper. In the Cast Calculus Cooper tends to function as a "love interest" to Oliver (analogous to Trip for Taylor and Franklin for Anna-Kat) although both characters are (or at least claim to be) straight and Oliver has had multiple girlfriends, most of whom are far less prominent as characters than Cooper is.
- Intergenerational Friendship: He becomes quite close to Spencer Blitz, enough for the older man to declare that Oliver is his family.
- Jerk with a Heart of Gold: Oliver can be a brat at times, but he cashed out his business partner, Viv's housekeeper Luz, using his cherished savings so she could return to her native country and be with her young daughter.
- Like Father, Unlike Son: A number of episodes highlight how his personality and quirks clash with Katie and Greg, particularly his desire to become rich. Greg admits he and Katie have discussed the possibility that Oliver was Switched at Birth.
- Mouthy Kid: In season 1. Talks back constantly to his parents and antagonizes his sisters, but does well in school, is an overachiever, and is generally level-headed and perceptive. Ages into a Deadpan Snarker.
- Only Sane Man: With the exception of when he is focused on money and/or wealth, Oliver is the most level-headed member of the family as he is able to see past and call out the quirks and eccentricities they display.
- Outnumbered Sibling: Oliver is the only boy in a family of three kids. Downplayed later on, when the Ottos increasingly take on Taylor's boyfriend Trip and Oliver's own best friend Cooper as surrogate sons.
- Screams Like a Little Girl: So much so that Katie mistakes Oliver's screams for Anna-Kat's, even after he hits puberty. (Made doubly funny because Daniel DiMaggio's voice dropped like a stone.)
- Surprise Pregnancy: Averted - of the three Otto children, he was the only one his parents deliberately tried for. In her more frustrated moments, Katie has openly lamented this.
- Young Entrepreneur: Oliver, upon finally realizing that his parents won't simply buy him whatever he wants, starts a lucrative career repairing and selling defective designer shirts and enlists the local housekeepers to to do the repair work.
The reason the Ottos are in Westport in the first place, their youngest child begins the series with OCD and is being treated for it at Westport Unified's special needs program. Katie's blatant favoritism toward Anna-Kat is a running gag throughout the series. As Anna-Kat matures she begins to grow out of her OCD and into what Katie hates most: a tweenage girl.
- All Girls Like Ponies: She desperately wishes own a pony and has a large collection horse-themed toys.
- Harmful to Minors: The reason she named the pet pig Hans Gruber is because Katie let her watch Die Hard.
- Mouthy Kid: Picks up Oliver's slack as he ages, and as she matures and her OCD begins to recede.
- Parental Favoritism: Katie makes it fairly obvious that Anna-Kat is her favorite, much to Taylor and Oliver's chagrin.
- Puppy Love: Her relationship with Franklin officially becomes a romantic one at the end of season 3, in "The Dance", when they are just nine years old (well, Franklin is nine-and-a-half, as Anna-Kat angrily informs Taylor). Anna-Kat had previously decided Franklin was her "boyfriend" in the season 2 episode "All Coupled Up" after Oliver got a new girlfriend of his own (leaving her as the only single Otto), but Franklin was in no way ready for even a "relationship" at that time and so it didn't take.
- Super OCD: The Ottos moved to Westport so that Anna-Kat could attend a local school with an excellent special needs program.
- Surprise Pregnancy: A classic "oops" baby, Anna-Kat is much younger than Taylor and Oliver. Katie blames Greg's latex allergy.
- Wounded Gazelle Gambit: Season 2 revealed she was actually more adept at doing things for herself than previously thought, but she pretended otherwise so she wouldn't have to.
Doris is an Asian-American friend of Katie, one of the few Westport housewives who will give her the time of day. As the series begins she is married to Richard, a very wealthy and aloof husband with whom she has several children whom she variably neglects or disciplines depending on her mood. Doris is gleefully lacking in scruples or morals, leading her own best friends to call her sociopathic.
- Berserk Button: Being called Japanese. Understandable, considering she's Korean.
- Children Are a Waste: This is what she feels about her unexpected pregnancy in Season 2 as it delays her plans to retire to a small Mediterranean island by several years, thus lowering her chances of still having her looks and seducing a well-built local when she finally does get there.
- Comedic Sociopathy: Multiple characters have acknowledged Doris as a sociopath. Even her own best friends acknowledge she's not a very good person. But the most prominent victims of her sociopathy (her husband and children) are seldom-seen (and the few times we see her husband Richard he's even less pleasant than she is), so we're able to laugh at how horrible she is.
- Education Mama: In classic Asian Tiger Mom fashion, Doris is intent on her children excelling in everything they do and exerts enormous pressure on them as a result.
- Freudian Trio: Doris is The Spock, usually giving the more practical (if ruthless and calculating) advice.
- Mrs. Robinson: After she and Richard divorce, she consistently expresses interest in much younger men, including Lonnie and Trip.
- Only One Name: We have yet to learn Doris's surname.
- Sitcom Arch-Nemesis: She seems to have a particular animus for Oliver, of all people. One suspects it's a case of "likes repel".
Angela is an African-American friend of Katie, a high-powered lawyer who is also a lesbian who cheated on her ex-wife, having joint custody over their children. Angela is a very laissez-faire parent who suggests to Katie that she should befriend her children and treat them as equals, and for this reason Katie usually ignores Angela's advice.
- Freudian Trio: Angela is The McCoy, generally giving the more compassionate, understanding advice (that Katie usually ignores).
- Lipstick Lesbian: She used to be married to a woman named Celeste and the divorce has not been amicable.
- New-Age Retro Hippie: She goes on silence retreats, she meditates, she regularly visits a psychic and likes to burn sage.
- Open-Minded Parent: Her child-rearing philosophy is to engage her children as equals and to acknowledge their wants and desires through intellectual discussion. Brief glimpses at her home life shows that this has failed spectacularly.
- Only One Name: Angela's surname was never revealed.
- Really Gets Around: Angela cheated on her ex-wife and since then has preferred to play the field, avoiding relationships and focusing on casual hookups. When circumstances force her to stay put with just one woman for just a few weeks, she becomes increasingly uncomfortable with the other woman's growing intimacy and attachment to her.
- Twofer Token Minority: A black lesbian, the only main character who fits either description.
- Where Da White Women At?: It could just be because it's Westport (where the only other woman of color is Doris), but every woman Angela's been involved with has been white. Her ex-wife Celeste is white, her extremely short-term love interest Chloe Brown Mueller was white, and, when pressed, Angela admits an attraction to Katie (and not to Doris, which rankles her something fierce). And after all, the pilot does have Katie and Angela messily making out to discourage a homophobic racist from moving in across the street.
Taylor's second boyfriend, a dumb jock a year older than her who is nonetheless incredibly sweet and devoted to her and gets along with all the Ottos (no mean feat). However, he is also idiotic to the point of appearing to have some difficulty functioning in real-world situations.
- Crazy Jealous Guy: Downplayed, but it's there. He gets intensely jealous whenever Taylor is even mistaken for interested in someone else, or when someone expresses an interest in Taylor. This backfires on him when he learns the truth about Pierce and confronts Taylor about it, but angrily demands she quit the play so as to avoid spending any more time with him, which she refuses to do.
- The Ditz: He seems to exist primarily to make Taylor, who barely has two brain cells to rub together herself, look smart by comparison.
- Dumb Jock: Although his athleticism isn't hugely emphasized most of the time, he is a jock and he is very, very dumb. It takes him two tries to graduate high school, and even then he has the lowest grade point average of any student in the graduating class.
- Family of Choice: This isn't as pronounced as it is with Cooper, but Trip is very attached to the Ottos and enjoys spending time with all of them. In turn, Trip might be the only outsider all of the Ottos actually like.
- Good Is Dumb: An exceptionally sweet, good-natured young man (even Katie likes him)... and a moron.
- Hidden Depths: Ordained to perform wedding ceremonies, which happened because he and Anna-Kat wanted two of her ponies to be married "for real", so he went online and got certified. This saves Katie's bacon when she needs a minister on super-short notice.
- Iconic Sequel Character: Trip is one of the few long-term recurring characters who didn't debut in the show's first season, instead making his first appearance in season 2. But he's logged more appearances on the show than anyone else not named in the opening credits.
- Odd Friendship: Genuinely close with Anna-Kat, the youngest Otto sibling.
- Satellite Character: Initially one to Taylor before he develops a close relationship with Anna-Kat.
Oliver's best friend, and the son of the wealthiest family in Westport. He isn't stupid, exactly, but he seems to have trouble comprehending what it means to not be able to afford whatever his heart desires. Cooper's parents are unseen characters who are constantly absent from his life, leading him to latch onto Katie (much to her own chagrin) as a surrogate mother figure. In season 5, after the Bradfords leave Westport to move to Palm Beach, they agree to let Cooper remain to finish his schooling there, and so he moves in with the Ottos.
- A Day in the Limelight: Before moving in with the Ottos in season 5, Cooper tended to average about one of these per season, where he's the focus of his own plotline and not just Oliver's Second Banana:
- "The Walk" in season 1, where Katie, annoyed that he's a terrible influence on her son, picks on him mercilessly; surprisingly, he's so touched by her refusal to defer to him as the son of the richest couple in town that he speaks on her behalf when all the other housewives accuse her of neglecting Anna-Kat after she lets her walk to the library on her own.
- "All Coupled Up" in season 2, where Cooper is the central character in the Friend Versus Lover plot when Oliver picks his new girlfriend Gina over him. He seeks out Katie to help him reform so that Gina (a girl from Branford who hates stuck up "Westport kids") will tolerate him spending time with Oliver. He doesn't really pull it off but Oliver's so touched by him trying anyway that he puts in a good word for him.
- "Insta-Friends" in season 3 finally shows his Stepford Smiler side after three years of pretending that his parents never being around doesn't really bother him, and he admits how much being Oliver's friend and the Ottos taking him in really means to him. From this point forward, he's much more open about his unhappiness with his home life.
- "Hip to Be Square" in season 4 has Cooper ready to tell his first serious girlfriend that he loves her, which Oliver protests, because they're both in lockstep in their relationships with their respective girlfriends and Oliver isn't ready to say it yet. Cooper eventually says it anyway after asking Katie and Greg for advice, only to get rejected and heartbroken. (This also means that Oliver's girlfriend dumps him as well - the girls were in lockstep too.) At the end of the episode, he says "I love you" to Oliver, and Oliver reciprocates.
- Cooper also gets to sing lead on one of the numbers in the Musical Episode.
- Family of Choice: The Ottos are this to Cooper, in lieu of his frequently absent parents.
- Fiction 500: By implication the Bradfords are this, being the richest family in a town full of insanely wealthy people. More concrete examples: the Bradfords have at least one house on every continent, and possibly more; they have multiple yachts; their son has exclusive access to his own private jet and a helicopter; their palatial estate has a bowling alley and an arcade with a full-time employee even though the place is usually empty; Cooper is able to buy and sell a Porsche as if he was shopping for clothes.
- Foil: Cooper is one to his best friend Oliver, having the thing Oliver wants most in the whole world (obscene wealth), but wanting the one thing Oliver has that he doesn't: a loving family.
- Freudian Excuse: He grew up being part of the richest family in town. That explains his poor people skills, but he says it's also why he doesn't care that Oliver is substantially poorer than he is. Everyone else is already poorer than he is, so he has no reason to care about stuff like that.
- Full-Name Basis: In early seasons, Cooper was usually referred to by his full name, even by his best friend Oliver. Even Cooper is known to call himself "Cooper B", even though we don't know of any other character named "Cooper". This is dropped in later seasons as he and the Ottos become more familiar.
- The Ghost: Cooper is mentioned several times before he makes his first appearance midway through season 1. His parents, whom Cooper mention constantly, have yet to make an onscreen appearance at all.
- Gratuitous Spanish: Frequently peppers his speech with phrases you'd hear in any introductory Spanish class. Lampshaded when, after someone responds to one of his Spanish salutations in kind, he has no idea what they're saying.
- Heterosexual Life-Partners: With Oliver. Although both characters are straight and have had girlfriends, Cooper acts as a surrogate "love interest" to Oliver in many plots, often grouped with Oliver's sisters' actual love interests, Trip and Franklin, and it's clear that their relationship with each other is the one that both of them value the most.
- Hidden Depths: The richest kid in town cares way less about class differences than a lot of the adults.
- History with Celebrity: Lisa Vanderpump is his godmother, and he makes use of this connection when the Ottos are vacationing in Los Angeles to arrange a meet-and-greet as a birthday present for Katie.
- Lonely Rich Kid: Double subverted. While he acknowledges his parents are always away, he often seems blissfully unaware of why that's a bad thing. Season 3's "Insta-Friends" shows this is more of a Stepford Smiler attitude; his parents bail on him at literally the last minute for a social function, and he suffers a major depression.
- Rich in Dollars, Poor in Sense: Often unaware of anything he says that might be insulting or out of touch.
A weird kid and a fellow student of Anna-Kat's in her special needs class. She is extremely fond of him, seeing in him what nobody else does.
- Ambiguous Disorder: Franklin's main "problem" is his complete lack of understanding social cues, which could describe any number of mental/social disorders.
- Cloud Cuckoo Lander: Franklin is weird. One episode shows he gets this from his mother, who informs Katie that she is a ghost. (Later on we learn she's joined a cult.)
- Color Blind Confusion: Admits he's this, which is why all of his "punch Porsches" are grey.
- Hidden Depths: Anna-Kat pleads with Oliver and Cooper to make Franklin over to impress her friends at her first "party for no reason" party, which turns out to be completely unnecessary when it turns out Franklin can play the piano and has the voice of an angel, which Anna-Kat never even knew about.
- Love Epiphany: In "The Dance", his initial Precocious Crush on Taylor wears off not because of Anna-Kat's ill-fated attempts at Operation: Jealousy, but because he sees Anna-Kat's date (Trip) kissing his own date (Taylor) - which is to say, kissing his girlfriend. He's irate at Trip two-timing "the greatest girl in the world"... and then he realizes.
- No Accounting for Taste: Anna-Kat absolutely adores him, for reasons which make sense only to her.
- Only One Name: Unlike Trip Windsor and Cooper Bradford, Franklin doesn't seem to rate a last name.
- Puppy Love: He and Anna-Kat have a very elementary school type "relationship" starting at the end of the third season. Anna-Kat calls him her "platonic childhood husband partner".
- Satellite Character: Is this to Anna-Kat.
Katie's mother, a retired flight attendant who spent much more time jet-setting than she did actually raising her daughter.
- History with Celebrity: Apparently the airline she worked for took on a lot of celebrity passengers, so she has a lot of stories about famous people from the '70s and '80s.
- It's All About Me: Kathryn always wants to be the center of attention.
- Lady Drunk: Kathryn is seldom seen without a drink in hand.
- Once a Season: Apart from a run in season 3 where she lived with the Ottos for a while, Kathryn generally appears once or twice a season.
- Parental Neglect: Kathryn was not a very good mother, and this informs the relationship between her and her now-adult daughter.
- Really Gets Around: Both in her heyday and in the present, Kathryn has been known for her promiscuity.
She moves in across the street from the Ottos in the pilot, an obnoxiously perky woman whom Katie instinctively dislikes. Still, she's the only Westport housewife other than Katie's friends who seems to genuinely like her.
- Glamorous Single Mother: Subverted in Season 3. She is a constant wreck and exhausted from the baby's needs, as well as regularly going to Katie for help. She considers getting back together with her ex just to take the pressure off.
- Token Good Teammate: For the rich women in town (excluding Doris and Angela). She's a snob and often thoughtless, but she's rarely malicious and actually likes Katie. Several of her appearances also portray her sympathetically, such as having a neglectful husband and a couple stepchildren who hate her.
A wealthy ex-convict who went to jail for insider trading, spending 20 years in the slammer. Upon his release he moves back home to Westport. He has no heirs, leading Oliver to befriend him and hope to be named his beneficiary.
- Cruel to Be Kind: He ultimately decides not to leave Oliver his millions. He knows that might seem harsh, but he feels that would rob Oliver of the joy of becoming rich on his own. Oliver agrees with this.
- Disco Dan: Still lives like it's The '80s. Justfied, as he'd been in prison for over 20 years and hasn't had much contact with the outside world.
- Expy: Of Gordon Gekko, Played for Laughs.
- Intergenerational Friendship: Develops one with Oliver, becoming a mentor to him.
- Killed Off for Real: Dies in the aptly titled episode "It's Hard to Say Goodbye".