Traditional sitcoms live or die on their casting, as each character must be precisely defined in order to quickly take root in the viewing public's imagination.

That challenge becomes even more complex when putting together an ensemble – as many of the greatest US sitcoms have – who are required to work in perfect harmony to strike comedic gold.

Rigorous audition processes and outright offers to A-list stars aid the quest for the perfect formula, which has proven to be genuinely priceless (artistically and commercially) in decades past.

Over the years, actors and behind-the-scenes creatives have revealed which of these fateful castings almost went differently. Would their respective shows have been as successful with these substitutions? That's for fans to debate and decide.

For your consideration, presents 11 of the most high-profile near-miss casting choices in sitcom history.

Matt LeBlanc almost played Phil Dunphy on Modern Family

Ty Burrell became a household name as sprightly estate agent Phil Dunphy in Modern Family – but the role could have been scooped up by a more established sitcom talent.

Friends icon Matt LeBlanc told USA Today that he had been offered the role of Phil during the show's early development, only to rule himself out of contention.

"[The script] came across my desk with an offer to play Ty Burrell's role," he began. "I remember reading it, thinking, 'This is a really good script, [but] I'm not the guy for this'."

When the now-legendary Modern Family cast was being assembled, LeBlanc was still in the midst of an extended acting hiatus following the relative failure of his Friends spin-off Joey.

He addressed the quiet period in an interview with The Hollywood Reporter: "When [Joey] was over, I just said, 'I don't want to do anything for at least a year'. And that turned into six years.

"I was enjoying myself... I really didn't think about work at all."

It would be showbiz satire Episodes that finally brought LeBlanc back to our TV screens, where he famously played a fictionalised version of himself.

When that series wrapped, his comedy comeback continued via traditional network sitcom Man with a Plan, whose protagonist is far closer to Joey Tribbiani than Phil Dunphy.

These later career choices indicate that LeBlanc feels best suited to masculine everyman roles, such as the one that made him famous. In fact, he hinted as much himself, with regard to declining Modern Family.

"I'd be doing the project an injustice to take this," he told USAToday. "I know what I can do, I know what I can't do."

Octavia Spencer almost played Donna in Parks and Recreation

Office manager Donna gradually became one of Pawnee, Indiana's most popular civil servants, appearing in more than 100 episodes of Parks and Recreation.

However, the character was initially only a rough outline of what comedian-turned-actor Retta, plus the show's celebrated writers, would eventually shape her into.

Donna's boundless confidence, intriguing personal life and appreciation for the finer things became fully formed traits by season 3 as the character's presence steadily grew.

But Donna's personality may have developed quite differently had future Academy Award winner Octavia Spencer bagged the part instead, and imbued it with her own flourishes.

At the time, Spencer was still a jobbing actress, picking up roles in everything from TV hit Ugly Betty to festive flick Bad Santa and Will Smith thriller Seven Pounds.

"I believe she got really far because I remember watching Octavia Spencer's audition," recalled Parks and Rec screenwriter Alan Yang on his retrospective podcast. "We were like, 'This is sensational. We love both of them'."

According to Yang, Retta's existing career in stand-up gave her the edge over Spencer as it showed that she was "comedy forward", although he wasn't privy to the intricacies of the decision.

Fortunately, the outcome of her Parks and Recreation audition didn't hinder Spencer's career one bit.

Danny DeVito almost played George Costanza on Seinfeld

George Costanza (played by Jason Alexander) proved to be the perfect comedic partner for Jerry Seinfeld on the latter's self-titled sitcom, with the pair sharing many a perfectly inane conversation over its nine seasons.

But things could have gone very differently. George was a struggle to cast, with several names being considered for the gig, including one actor with a passing resemblance to the final choice.

Danny DeVito had recently become a major star after his successful run as Louie De Palma in '80s sitcom Taxi, which had opened the door to film roles in Terms of Endearment, Romancing the Stone and Twins, among others.

With that in mind, it was somewhat ambitious of producers to think they could lure him back to the small screen so soon. At least, that was the assessment of Alexander himself.

While discussing the alternate options for George Costanza with US radio host Howard Stern, the actor speculated on DeVito's reasoning for turning the show down.

"I think in the case of Danny he probably didn't want to be... his career, when we started Seinfeld, would've been at its apex, so he probably didn't want to do a sidekick role," he said.

For Alexander, a little-known actor when Seinfeld began, the role proved a perfect fit, earning him a place in the pantheon of iconic sitcom actors.

He would return to the genre in later years for guest roles in the likes of Friends, Malcolm in the Middle, The New Adventures of Old Christine (a reunion with Seinfeld co-star Julia Louis-Dreyfus) and Community.

Notably, he also took a recurring role in the second season of Everybody Hates Chris, a series loosely based on comedian Chris Rock's teenage years. According to Alexander himself, Rock was another alternate choice for the role of George (via Really No Really Podcast).

Lucy Hale almost played Hannah Montana

Hannah Montana will forever be known as the Disney Channel show that catapulted then-teenager Miley Cyrus to global fame.

The children's sitcom clearly drew liberal inspiration from the actor and musician's real life, casting her as a character named Miley, who happened to be the daughter of country singer Robby Ray (portrayed by her actual dad, Ray).

But Hannah Montana wasn't built from the ground up with Cyrus in mind.

Rather, as Time Magazine reported, it was a "cast-contingent" commission, meaning the concept of schoolgirl-by-day/celebrity-by-night was approved – but its fate rested on finding an appropriate teen idol.

Casting directors were seeking a rare combination: a teenage girl with advanced musical talent, who could be seen as 'cool' by youngsters without scaring off their parents – or causing any real-world PR headaches.

A year-long search ended in Hannah Montana being temporarily "shelved", with Cyrus herself being turned down for being too young. After intense lobbying, producers changed their minds.

In an interview with BuzzFeed just last year, Pretty Little Liars alum Lucy Hale revealed she was one of the unsuccessful applicants during that frenzied search for Hannah Montana.

"I remember the audition – it was a taped audition in Tennessee," she revealed. "It was the audition that made me want to be an actress. I remember that vividly. It was very cool."

Hale harbours no regrets, believing that Miley's casting was "meant to be", with her own breakthrough role of Aria in Pretty Little Liars coming just a few years later.

Infamously, Cyrus would later go to great lengths to distance herself from Hannah Montana, during an era of provocative music videos and live performances – including a headline-grabbing medley with Robin Thicke at the 2013 MTV Video Music Awards.

To be fair, the daring media strategy did work, pivoting her to a successful adult career independent of the Disney Channel series.

William H Macy almost played Brian in Family Guy

Family Guy made Seth MacFarlane a big name, establishing his frequently crude and outrageous comedic voice – or should that be ?

In addition to creating the warped series, Macfarlane voices three of the main characters: slobbish patriarch Peter Griffin, his scheming infant Stewie, and academic dog Brian.

It wasn't his intention to pull triple-duty in the Family Guy cast, however, with a highly regarded actor being considered for Brian as the series neared its 1999 launch.

Fresh off a four-year stint on medical drama ER and an Academy Award nomination for darkly comic drama Fargo, William H Macy taped an audition for the Griffin family pet.

"I can't remember why, but we did audition that character... There were actually some cool people – at one point, William H Macy auditioned for Brian," MacFarlane told IGN, back in 2003.

Macy's take on Brian was included in the final selection reviewed by network executives, but they opted to keep MacFarlane's dulcet tones for the pretentious pooch.

The series creator theorised that he gained an advantage as his own audio was used as a placeholder in the unaired pilot, to which higher-ups became accustomed.

"It was the fact that they had heard Brian that way in the initial pilot, and at that point they were used to hearing him that way," he said. "I think they just didn't want to mess with it."

In 2020, MacFarlane took part in an Instagram interview with his The Orville co-star Jessica Szohr, who had also worked with Macy in the long-running US adaptation of Shameless.

There, he expressed some embarrassment over not fighting harder for Macy's casting.

He said: "I look back and I'm like, 'How cocky and arrogant must I have been at 24 to have Bill Macy audition for Brian and go, 'You know what? I don't think it's working and I'm going to do it myself'? The hubris is not to be believed!"

Macy would go on to scratch his animation itch elsewhere, taking voice roles in Superman: The Animated Series, Batman Beyond, The Wild Thornberrys and Curious George.

Macauley Culkin almost played Leonard in The Big Bang Theory

The Big Bang Theory might never have enjoyed the critical acclaim of other sitcoms on this list, but there's no arguing with its impact.

By its finale in 2019, the series was still pulling in upwards of 17 million viewers, and its main cast members were earning $1 million per episode (reminder: there were 24 in season 12).

It's an envious pay cheque indeed, which is why it might sting to have turned the show down in its infancy. Alas, that was the decision of Home Alone alum Macauley Culkin.

During an appearance on the Joe Rogan Experience back in 2018, he revealed that he'd been aggressively "pursued" for the role of Leonard Hofstadter – ultimately played by Johnny Galecki.

Culkin explained that he'd been unimpressed by the premise of the sitcom, which he recalls being pitched as: "These two astrophysicist nerds, and a pretty girl lives with them – yoinks!"

"I was like, 'Yeah, I'm cool, thanks'," the actor continued. "And then they came back at me again, and I said, 'No, no, no. Again, flattered, but no'.

"Then they came back at me , and even my manager was, like, twisting my arm."

At the time, Culkin was prioritising edgier projects as he made the difficult transition from child star to adult actor.

These included black comedy films Saved! (with Mandy Moore) and Sex and Breakfast (with Eliza Dushku) as well as an experimental semi-autobiographical book titled Junior.

In comparison, The Big Bang Theory might have seemed a tad safe or twee, which appeared to be exactly what Culkin was peddling away from.

On the aforementioned podcast, he concluded: "I'd have hundreds of millions of dollars right now if I did that gig. At the same time, I'd be bashing my head against the wall."

Leonard proved a perfect fit for Galecki, who gave a star-making turn after almost two decades of smaller roles in the likes of Christmas Vacation, Roseanne, Vanilla Sky and Hope & Faith.

Bob Odenkirk almost played Michael Scott in The Office (US)

Two gifted comedy actors were on the cusp of superstardom in the mid-noughties, but only one could bag the role of a lifetime: Michael Scott in The Office (US).

Of course, we all know what happened!

Steve Carell was chosen as David Brent's American counterpart, at a time when his profile was rapidly growing thanks to hilarious film roles in Bruce Almighty, Anchorman and The 40-Year-Old Virgin.

Just as Carell had initially gained attention on The Daily Show, his main competitor for the role of Michael Scott was also a promising sketch performer.

Years before he'd flex his dramatic muscles in Breaking Bad and its spin-off Better Call Saul, Bob Odenkirk had earned buzz for a writing stint on Saturday Night Live and HBO's Mr Show, devised alongside David Cross (Arrested Development).

Clips of Odenkirk's audition have since surfaced online as artefacts of intrigue, although fans seem content that TV history unfolded correctly.

Odenkirk himself joined that consensus during a 2024 appearance on the Office Ladies podcast, hosted by sitcom alumni Jenna Fischer and Angela Kinsey.

"I am, in a strange way, a very earnest person for a person in comedy," he commented, while diagnosing why the job slipped through his fingers.

"I am oddly earnest… It's one of the reasons I think Steve Carell is the one who got the role... he's better at being genuinely fun."

Odenkirk continued: "I think I bring with me a little bit too much earnest seriousness... and there's nothing I can do about it except play other roles where it's helpful to have that.

"You just don't believe me as a purely light character. You just are looking for the darkness, and that's actually great in drama – that's a plus! But in comedy, it's not a plus."

Odenkirk would go on to guest star in The Office season 9 as a Michael Scott-style boss at another company, who gives Pam (Fischer) an uncanny sense of déjà vu. The role was a nod to his unsuccessful audition.

Not long after, co-star Rainn Wilson shared a revealing snap of the sign-in sheet on audition day for The Office (via Facebook) – unveiling more near-miss Michaels that never saw the light of day.

Those include Wilson himself, who auditioned for both Michael and Dwight (the role he secured), plus Ben Falcone (Bridesmaids), Alan Tudyk (Andor), Bill Chott (Wizards of Waverly Place) and the late comedian Jim Zulevic.

Stephanie Beatriz almost played Santiago on Brooklyn Nine-Nine

Brooklyn Nine-Nine would be unimaginable without Rosa Diaz (Stephanie Beatriz), the tough-as-nails, straight-talking detective with a temper.

But the character wasn't envisioned with Beatriz in mind, or anyone who looked remotely like her, as Rosa had initially been named 'Megan' and imagined as a white woman.

The description had dissuaded Beatriz, a total unknown at this time, from going up for the role, leading her to fight for Amy Santiago instead – against eventual co-star Melissa Fumero.

But when Beatriz came in for her audition, the casting director clearly saw that she could excel in the 'Megan' role, asking her to read for both in her callback.

"I got a screen test for both," she remembered (via BUILD Series). "At the screen test, I did the Amy role first and I was really nervous... when I got there, they were like 'by the way, you're going to be improvising with Andy Samberg'.

"I don't think that screen test went very well, but I also think that role was always meant to be Melissa's, and it's just so lucky that I got to read for it because then I got to read for this other role: 'Megan'."

When Beatriz got word that Fumero had been cast as Amy Santiago, she assumed that she would be out of contention for 'Megan', given that US network shows rarely had two Latina characters.

"It doesn't happen, there's only one of us, ever," she thought, before her agent called with a major surprise. The rest is history!

Jason Biggs almost played Ted in How I Met Your Mother

How I Met Your Mother's legacy may have been slightly tarnished by its much-maligned ending, but the show was still an unquestionable commercial success.

The salaries never climbed to such dizzying extremes as The Big Bang Theory, but most of the cast were on a whopping $225,000 per episode by season 9 – while Neil Patrick Harris negotiated an even grander $400,000 pay cheque.

Nice work if you can get it, which is perhaps why American Pie alum Jason Biggs considers turning down an offer to play Ted Mosby as the "biggest regret" of his career.

Explaining himself during a 2021 appearance on SiriusXM, Biggs said: "I was in a phase of— it sounds so obnoxious to say right now – but, at the time, it was like, 'Okay, do I want to do TV?' I don't know that I was quite ready to go that route."

It's worth mentioning that, in early 2005, when casting would have been underway on HIMYM, there was a much clearer distinction between film and television than exists today.

The era of Hollywood A-listers lining up for prestige streaming shows was still years in the future, while Biggs was riding high from the first American Pie trilogy (which cumulatively made $750 million at the global box office).

It's understandable, then, that he might have held out for more hit comedy films, but alas, the genre as a whole would largely migrate to streaming over the next two decades.

"Big picture, I have no regrets, right? I'm very lucky, very fortunate," continued Biggs. "I'm still here! That's number one.

"But yeah, if I had to pick out something I wish I had done differently, I would've taken that gig, for sure."

Instead, the role went to Joshua Radnor, an unknown at the time of his casting, who went on to star in more than 200 episodes over the next nine years.

Biggs' American Pie co-star Alyson Hannigan – already well-acquainted with network television from her time on Buffy the Vampire Slayer – would take up a spot in the CBS sitcom as Lily.

If Biggs had signed on to play Ted, it's interesting to wonder whether Hannigan's role might have gone elsewhere, as reuniting both actors so soon could have made HIMYM appear derivative of American Pie.

Jon Favreau almost played Chandler in Friends

Friends fans with good taste all know that Monica and Chandler were the most compelling, least toxic couple on the long-running sitcom. But Courteney Cox's on-screen husband wasn't necessarily destined to be the late, great Matthew Perry.

Among several actors considered for the role was none other than Jon Favreau, who would later join the show as Pete Becker – an eccentric millionaire whose romance with Monica was cut short by his agonising fixation on the UFC.

According to Vulture, Favreau was more interested in becoming a filmmaker than an actor. His directorial debut, Swingers, launched not only his own career, but that of another Friends near-miss.

Casting director Ellie Kanner (via HuffPost) revealed that Vince Vaughn had been considered for the role of Chandler's best friend and flatmate, Joey Tribbiani.

She described the 20-something Vaughn as "handsome and tall" and "a good actor," but not quite the right fit.

Favreau and Vaughn's fates would become intertwined with 1996's Swingers, where they played unemployed actors chasing their big break in Hollywood. In other words, not a world away from the life they knew at that time.

But the film's critical and commercial success changed all that, with Favreau going on to direct the likes of Elf, Iron Man, Chef and The Mandalorian, while Vaughn had a strong run of comedy hits including Old School, Dodgeball and Wedding Crashers.

In this case, everyone emerged a winner, including us at home, who got to enjoy a decade of endlessly quotable lines from Perry's Chandler Bing. A sitcom legend, forever.

Hugh Grant almost replaced Charlie Sheen on Two and a Half Men

Hit sitcom Two and a Half Men was in a precarious spot when leading man Charlie Sheen relapsed into substance abuse and had a major falling out with boss Chuck Lorre.

In the wake of Sheen's firing, producers were desperately seeking a way to keep this highly profitable ratings juggernaut on the air – and that included approaching big-name actors with very little actual information.

Hugh Grant confirmed as much, in a 2016 interview with radio host Howard Stern.

"They talked to me about [Two and a Half Men], but the problem was they didn't have a script or a new character – they just said, 'Trust us, we'll create one'," he recalled.

Grant chalked up the rather frantic scramble for a star to the "very tight schedule" that American network television runs to, with lucrative advertising deals and cast contracts on the line.

Despite being offered a "stratospheric" sum of money to become the new face of Two and a Half Men, Grant told producers that it would be "very difficult" for him to agree without knowing precisely what he'd be performing.

"I said, 'Well, you're obviously brilliantly talented', because I like that show, and they make brilliant TV shows, really. But I said, 'I'm too scared to sign up without a script'," he explained.

Pushed for a verdict on the show's second life – in which Ashton Kutcher played billionaire Walden Schmidt – Grant said that it was still "very good", but remained unconvinced whether his own tenure would have succeeded.

"What they created for Ashton Kutcher was clearly something completely different from what they would have created for me," added Grant. "So it's hard to judge [whether it would have worked out]."

The whole experience opened Grant's eyes to the sky-high salaries of US sitcoms in the 2000s and early 2010s.

It led him to wonder whether The Big Bang Theory's Simon Helberg (aka Howard), his co-star in musical biopic Florence Foster Jenkins, might be "the richest man I've ever met".

With linear TV ratings declining, and sitcoms struggling to find an audience on streaming, those wages may never again be seen by the genre.

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