Many movie genres can cross over into comedy, like romcoms, horror-comedies, dramedies, and action-comedies. However, R-rated single-genre comedies focus almost entirely on humor. Furthermore, their MPAA rating lets the people behind the movies push the envelope to write any kind of joke they want to include.

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R-rated comedies like The Hangover and Step Brothers define the decade's humor which would spill out to the 2010s. Early 2000s comedies like Jay and Silent Bob Strike Back ushered out certain troupes made popular during the late 1990s. Some fans take to Letterboxd to rank the best comedies of the 2000s. Others have used IMDb to rate their favorites, and the best single-genre R-rated comedies of the 2000s are revealed based on score and number of votes.

Me, Myself & Irene (2000) —6.6

The Farrelly brothers give audiences a Jim Carrey-starring dark comedy with Me, Myself & Irene. It follows the story of Carrey's Charlie Baileygates who deals with a split personality after bottling up his emotions for years. Along the way, he links up with Renée Zellweger's Irene P. Waters, who faces conflict with both Charlie and his alter-ego Hank Evans.

Fans of the movie might point to Jim Carrey's trademark signature physical comedy as part of the reason why it's so highly rated. Others might say Me, Myself & Irene is the best Farrelly brothers comedy of the 2000s. Critics might say its dark humor is less accessible than other 2000s single-genre R-rated comedies of the decade.

Jay and Silent Bob Strike Back (2001) — 6.8

Jay kissing Justice in a fantasy in Jay and Silent Bob Strike Back.

Director Kevin Smith gave fans the first movie focusing on his celebrated side characters with Jay and Silent Bob Strike Back upon its release. The movie follows the two on a road trip to Hollywood. They find out a movie is coming out starring characters based on their likenesses. They set out to obtain royalties from the film and get wrapped up in a few different adventures along the way.

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Jay and Silent Bob Strike Back nods to several other films in Smith's View Askewniverse. Audiences might say it has a built-in fan base for those who follow the cult director. Fans perhaps say its large cast of comedians, actors, and celebrity cameos make the movie fun and entertaining. Others may point to its sequel Jay and Silent Bob Reboot as evidence of its legacy.

Role Models (2008) — 6.8

Paul Rudd in Role Models

Many fans say Role Models is one of director David Wain's best movies. It tells the story of Paul Rudd's Danny and Seann William Scott's Wheeler. Danny and Wheeler are energy drink spokespeople who are forced into a "big brother" program after getting into legal trouble.

Role Models is one of Wain's most accessible comedies. Fans might point to the hilarious performances of its stars and co-stars like Jane Lynch and Ken Marino for its high rating. Others might say the unique script makes for several funny moments. Some audiences perhaps say the movie is simple, sweet, and consistently hilarious.

Step Brothers (2008) — 6.9

Fans remember Step Brothers as one of the funniest movies of the 2000s. The movie showcases Will Ferrell and John C. Reilly as titular stepbrothers Brennan Huff and Dale Doback. They are 40-year-olds who still live with their single parents, and after they get together, they are forced to live in the same house. As they enter adulthood late, they face the difficulties of grown-up responsibilities.

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Step Brothers is highly-rated for many reasons. Fans might point to the hysterical performances of its main stars, but also its supporting castmembers like Adam Scott, Richard Jenkins, and Kathryn Hahn. Others remember Step Brothers' hilarious quotes. Some might just say the original script makes for non-stop situational comedy.

Old School (2003) — 7.1

The Old School movie poster.

Old School is the highest-rated college single-genre R-rated comedy from the 2000s on IMDb. It follows Luke Wilson's Mitch Martin. Mitch starts a fraternity with some of his friends, even though they have all been out of college for about ten years. Will Ferrell and Vince Vaughn star alongside Wilson as his pals Frank "The Tank" Ricard and Bernard "Beanie" Campbell who help gather up a ragtag group of pledges.

Fans of the movie might say Old School features some of the most prominent comedic actors of the time. Others perhaps say the college comedy has always been ripe for funny moments, and Old School is no different. Critics of the movie perhaps say the fraternity setting makes the movie hold up less well than some other higher-rated R-rated comedies from the 2000s.

Borat (2006) — 7.3

Borat Goes America

Borat is the highest-rated 2000s R-rated single-genre R-rated comedy mockumentary on IMDb. It was a sensation upon its release. It showcases Sacha Baron Cohen's titular character Borat Sagdiyev in his first trip to the United States. It features Borat's real-life interactions with Americans across the country, and the segments are tied together with a loose plot.

Fans might say Borat's legacy is evident considering its 2020 sequel Borat Subsequent Moviefilm and the cultural impact of the character. Others might say that Borat is a 2000s comedy that aged surprisingly well, despite the several controversies it sparked upon its release.

Clerks II (2006) — 7.3

Dante and Randall return in Clerks II

Clerks II is the follow-up to director Kevin Smith's first feature film Clerks. Set a decade after the events of the first 1994 film, it follows up on the story of protagonists Dante Hicks and Randal Graves. They begin working at a fast-food restaurant after the Quik Stop convenience store showcased in Clerks burns down.

Clerks gained a cult following after its release, so its little surprise fans flocked to see the sequel twelve years later. Viewers perhaps rate it highly because it displays Kevin Smith's trademark humor and brings back some of his celebrated characters. Audiences have rated it highly among R-rated single-genre comedies of the 2000s.

Death At A Funeral (2007) — 7.4

Alan Tudyk screaming Death at a Funeral

2007's Death At A Funeral is a British comedy. It showcases a family during a funeral where several mishaps occur. A hallucinating family member, awkward reunions, and blackmailing relatives come together for several funny situations. The events of the film unfold over one day during what is supposed to be a solemn ceremony.

Fans might point to the originality of the script when considering the high rating of Death At A Funeral. Audiences perhaps refer to the comedy's unlikely setting of a funeral as one perfect for black comedy. Death At A Funeral's effectiveness is underscored by its 2009 Hindi remake, 2010 American remake, and 2010 Kannada remake.

Superbad (2007 ) — 7.6

Fogell, Seth, and Evan in Superbad talking

Superbad showcases Jonah Hill's Seth and Michael Cera's Evan in a coming-of-age romp from a script co-written by Seth Rogan and Evan Goldberg. It follows the protagonists on their journey to a year-end house party in the final days of high school. Along the way, they run from cops, are threatened by peers, and pursue their crushes.

Fans perhaps say Superbad is one of the best comedy movies of the 2000s. It brings a funny script and raunchy ad-lib exchanges together to present a memorable comedy. Some viewers might say Superbad is both funny and sweet, ending on a warm note and accurately representing the experience of high school in the late 2000s in American suburbia.

The Hangover (2008) — 7.7

Alan, Phil, and Stu ride an elevator in The Hangover

The Hangover is the highest-rated single-genre R-rated 2000s comedy on IMDb. The movie presents the story of a bachelor party gone wrong when its attendees wake up in a chaotic situation with no memory of how it came to be. Bradley Cooper, Ed Helms, and Zach Galifianakis star in the Las Vegas-set comedy.

The legacy of The Hangover speaks for itself. It spawned two sequels, a massive fanbase, and accolades like a Golden Globe for Best Comedy or Musical upon its release. Audiences might point to its performances for its high rating. Others perhaps say the script makes for hysterical moments thanks to its production and plot. Its cultural impact underscores The Hangover's popularity.

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