Farrell was born in Castleknock, Dublin, Ireland, the son of Rita (née Monaghan) and Eamon Farrell. His father played football for Shamrock Rovers FC and ran a health food shop. His uncle, Tommy Farrell, also played for Shamrock Rovers. Farrell has an older brother, Eamon, Jr., and two sisters, Claudine and Catherine. Claudine works as his personal assistant. Farrell was educated at St. Brigid's National School, followed by secondary school at Castleknock College, and then Gormanston College in County Meath. He unsuccessfully auditioned for the Irish musical group Boyzone around this time.
Farrell was inspired to try acting when Henry Thomas' performance in E.T. the Extra-Terrestrial moved him to tears. With his brother's encouragement, he attended the Gaiety School of Acting, dropping out when he was cast as Danny Byrne on Ballykissangel, a BBC drama about a young English priest who becomes part of an Irish rural community. As an 18-year-old travelling in Sydney, he was at one time suspected for attempted murder. The police sketch looked remarkably like him and he had even described blacking out during the night in question. His only alibi was apparently a journal kept by his friend that explained the two had been across town that night, taking MDMA.
Farrell had roles in television shows and films, including Ballykissangel and Falling for a Dancer in 1998 and 1999. He made his feature film debut in English actor Tim Roth's directorial debut The War Zone, a drama about an incident of child abuse, starring Ray Winstone and Tilda Swinton as parents of a girl Farrell's character (Nick) dates. Farrell also appeared in Ordinary Decent Criminal with Kevin Spacey and Linda Fiorentino, a film loosely based on the life of Martin Cahill. In 2000, Farrell was cast in the lead role of Private Roland Bozz in Tigerland, an under-released film directed by American Joel Schumacher. He reportedly got the part on the basis of his charm. Emanuel Levy of Variety said that Farrell "shines as the subversive yet basically decent lad whose cynicism may be the only sane reaction to a situation". Michael Holden of The Guardian wrote that Farrell was "too much the hero" to fit the classic rebel archetype properly, but he did not mind. Tigerland earned $139,500.
Farrell's next American films, American Outlaws (2001) and Hart's War (2002), were not commercially successful. His 2002–2003 films, including Phone Booth, The Recruit and S.W.A.T. (all thrillers, with the former two his first starring roles), were well received by critics and successful at the box office. Of Phone Booth, Ebert wrote that it is "Farrell's to win or lose, since he's onscreen most of the time, and he shows energy and intensity". Philip French of The Observer praised Farrell's performance. In S.W.A.T., the actor starred in an ensemble cast including Samuel L. Jackson, Michelle Rodriguez, Olivier Martinez and Jeremy Renner; Renner became a friend. Alan Morrison of Empire wrote, "Farrell can usually be relied upon to bring a spark to the bonfire. That's also true of [this movie]." Elvis Mitchell of the New York Times criticised Farrell's accent, writing that he "employ[ed] a wobbly American accent that makes him sound like an international criminal a step ahead of the authorities". Ebert and the New York Times's A.O. Scott disagreed on the actor's effectiveness in The Recruit; Ebert noted the actor's likability, but Scott felt that Farrell "spends his time in a caffeinated frenzy, trying to maintain his leading-man sang-froid while registering panic, stress and confusion". Phone Booth earned $46.6 million, S.W.A.T. $116.9 million and The Recruit $52.8 million at the box office.
Farrell's supporting roles include an ambitious Justice Department agent opposite Tom Cruise, a potential criminal in Minority Report (2002), and the villain Bullseye in Daredevil (2003). Matt Damon was originally offered the Minority Report role, turning it down to appear in Ocean's Eleven. Farrell said "he had no problem" being the producer's fallback after Damon declined. Bullseye is an assassin, proud of his accuracy. Farrell was signed to the role in December 2001, although he was considered for the lead role of Matt Murdock (Daredevil) until Ben Affleck signed. Farrell was encouraged to keep his Irish accent, since this version of Bullseye is from Ireland. He read Frank Miller's Daredevil comics to understand Bullseye "because the expression on the character's faces in the comic books, and just the way they move sometimes, and the exaggerations of the character I'm playing...he's so over-the-top that you do draw from that. But it's not exactly a character you can do method acting for...you know, running around New York killing people with paper clips". That year, he was voted sixth World's "Sexiest Man" by Company magazine.
In late 2003 Farrell starred as a criminal who plots a bank robbery with Cillian Murphy in the dark comedy Intermission, which held the record for highest-grossing Irish independent film in Irish box-office history for three years and remains a cult classic there. In 2004, he appeared in several other independent films receiving limited theatrical release in most countries, including A Home at the End of the World (adapted from Michael Cunningham's A Home at the End of the World). Roger Ebert praised Farrell, saying that he was "astonishing in the movie, not least because the character is such a departure from everything he has done before". Mick LaSalle of the San Francisco Chronicle differed, saying that the actor "is keen on making good....The effort is there, but it's a performance you end up rooting for rather than enjoying, because there's no way to just relax and watch".
Farrell played the title role of Alexander the Great in Oliver Stone's 2004 biographical film Alexander, which, while receiving some favourable reviews internationally, was poorly received in the United States. Its portrayal of the conqueror as bisexual was controversial; the film was criticised by some historians for its treatment of the ancient Persians, although others praised it for its accuracy. An ancient-history scholar at the University of Nebraska wrote:
The film grossed $167 million worldwide, just exceeding its budget of $155 million.
Farrell's next film was 2005's Academy Award-nominated The New World, his second historical epic. He played the lead role of Captain John Smith, the founder of 17th-century colonial Jamestown, Virginia who falls in love with the Native American princess Pocahontas (Q'Orianka Kilcher). Director Terrence Malick went out of his way to keep Farrell and Kilcher apart until they were filmed together. Although it was released in only 811 theatres worldwide and had a relatively low box-office gross, the film received a large number of positive reviews. In one of four reviews in The Guardian, John Patterson described it as a "bottomless movie, almost unspeakably beautiful and formally harmonious". The New World was followed by Ask the Dust, a period romance set in Los Angeles based on a John Fante novel and co-starring Salma Hayek. Reviews were mixed; Manohla Dargis of The New York Times favourably described Farrell's work, but Peter Bradshaw of The Guardian found "something a little forced in both lead performances". With a limited theatrical release, it was not a financial success.
The actor was more successful in 2006 with his role opposite Jamie Foxx in Michael Mann's action crime drama, Miami Vice. The film grossed $164 million worldwide on a budget of $135 million, and TimeOut New York ranked it among the top 50 movies of the decade. (The DVD, released the same year, also managed to sell over a million copies (equivalent to $7.91 million in pirated versions) in its first week alone., and, as of 11 February 2007, had grossed over $36.45 million in rentals. A. O. Scott criticised Farrell's work: "When he's not on screen, you don't miss him, and when he is, you find yourself, before long, looking at someone or something else." Conversely, Peter Travers of Rolling Stone was enthusiastic. The actor also reportedly took a slight pay cut to make friend and recent Oscar winner Jamie Foxx happy: His salary was initially larger than Foxx's.
Farrell next appeared in Woody Allen's Cassandra's Dream, which premiered in 2007 and was distributed in the US in early 2008. Reviews were mixed, with Maitland McDonagh of TV Guide writing that Allen's work was "shallow and unconvincing from beginning to end" and Mick LaSalle of the San Francisco Chronicle saying that although "it's not as good as Match Point or Crimes and Misdemeanors...taken on its own, it's a fairly impressive piece, a directorially vigorous, well-acted, tightly constructed movie". LaSalle praised Farrell: "Allen is notorious for not giving his actors explicit instructions, and yet somehow this worked wonders for Farrell, who has never seemed so naked, so clear and so unencumbered as he does here." Manohla Dargis concurred in the New York Times, adding that she thought Farrell was well-matched with co-star Ewan McGregor.
Farrell's next film, Martin McDonagh's first full-length feature In Bruges, opened the 2008 Sundance Film Festival. While the New Yorker and TimeOut London's film critics found co-star Brendan Gleeson's performance the stronger of the two, Bradshaw of The Guardian found Farrell (as hitman Ray) "absolutely superb: moody and funny, lethally sexy, sometimes heartbreakingly sad and vulnerable like a little boy". Time called the film "the prettiest bloodbath of 2008", and Farrell received his first Golden Globe.
Shortly thereafter he appeared in Kicking It, a documentary following six homeless men from Kenya, Russia, Afghanistan, Ireland, Spain and the US as they attempt to qualify for the Homeless World Cup. Farrell appeared on screen and provided the narration, donating his earnings to a homeless shelter in Ireland. The film was released simultaneously in theatres and on television, airing on ESPN2 in a very short window before its DVD release. Farrell received positive reviews for his involvement in the true story.
Later in 2008 Farrell was brother-in-law to Edward Norton's character in Pride and Glory, a police drama directed by American Gavin O'Connor. Roger Ebert disliked the film and A. O. Scott said that the actor "once again indulges his blustery mixture of menace and charm, overdoing both," but Gregory Kirschling of Entertainment Weekly liked Farrell's work.
On 11 January 2009, Farrell won the Golden Globe Award for Best Actor – Motion Picture Musical or Comedy for In Bruges, in which he co-starred with Brendan Gleeson. That year he also appeared in Terry Gilliam's film The Imaginarium of Doctor Parnassus, starring Christopher Plummer and Andrew Garfield. Farrell was one of three actors (with Johnny Depp and Jude Law), who helped complete Heath Ledger's role when Ledger died before filming ended. They played "Imaginarium" versions of Ledger's character Tony, donating their earnings to Ledger's daughter Matilda.
Farrell also starred that year in Triage, directed by Oscar-winning Bosnian screenwriter and director Danis Tanović, about the life of a war correspondent. He lost 30 pounds for the role. The actor's work was described as "dedicated" by Variety's Todd McCarthy, and Julian Sancton of Vanity Fair wrote that the film was "a hell of a lot more insightful than other movies that deal with a similar topic". However, Triage was not widely distributed due to the marketing challenges posed by its difficult topics (including PTSD). That year, Farrell played a supporting role (as Tommy Sweet) in Crazy Heart with Jeff Bridges.
Another 2009 release was Ondine, a fantasy-drama directed by Neil Jordan starring Farrell as a fisherman with a handicapped daughter. Shot in the village of Castletownbere on Ireland's southwest coast, it featured cinematography by longtime Wong Kar-wai collaborator Christopher Doyle. Mary Pols of Time magazine called the role "tailor-made for Farrell", saying that the actor gave a "beautifully confident performance". Todd McCarthy of Variety singled Farrell out, noting that he worked well as an ensemble actor "graciously allowing [child star Alison Barry] to steal every scene she's in".
The next year, Farrell starred with Keira Knightley in the crime romance London Boulevard. The film, American William Monahan's debut as director after writing screenplays for The Departed and Body of Lies, was panned by critics. Peter Bradshaw of the Guardian wrote that the film "uses up all its energy, wit and ideas in the first 20 or so minutes, before collapsing into a flurry of boring violence". Leslie Felperin of Variety described it as "like a fancy, retro-styled pocket watch that someone accidentally broke and tried to reassemble with only a vague idea of clockwork". Felperin thought the stars' work was frail, with Farrell "mostly taciturn and vacuous."
The actor starred in the 2011 comedy Horrible Bosses, directed by Seth Gordon, with Jennifer Aniston, Jason Bateman, Charlie Day, and Jason Sudeikis. The film focuses on a trio of employees who plot to murder their tyrannical superiors. The London Observer's Mark Kermode wrote that although the film would have benefited from a tighter script, Farrell and Jamie Foxx had juicy roles which they "riff with panache". Michael Phillips of the Los Angeles Times wrote that Farrell brought "massive, slobby relish" to his role as Sudeikis's cocaine-fiend boss.
Later that year, Farrell played the main antagonist in the Fright Night remake, joining Anton Yelchin, David Tennant and Toni Collette in the story of a charismatic vampire who moves next door to a high-school student and his single mother. The film was released by DreamWorks, with Craig Gillespie (of Lars and the Real Girl) directing a script by Buffy the Vampire Slayer writer Marti Noxon. Sukhdev Sandhu of the Telegraph wrote that Farrell "proves his comedy credentials once more....utterly seductive as the plushly eyebrowed carpenter-cum-bloodsucker", while the New York Times's A.O. Scott thought that Farrell played his role with "a wink and a snarl and a feline purr". Logan Hill of New York magazine, on the other hand, was confused by the actor's performance: "Sure, [it] may not make much sense, but neither do centuries-old vampires living in Nevadan subdivisions. So he goes for it."
Farrell starred with Kate Beckinsale in Columbia Pictures' Total Recall, a 2012 remake of the 1990 film with Arnold Schwarzenegger. Filmed from May to September 2011 in Toronto and directed by Len Wiseman, the film was a new sci-fi take about a sleeper agent. Costar Jessica Biel appreciated Farrell's skills, calling the actor "surprising and exciting. He just has the ability to be trying different things all the time." Roger Ebert and the New York Times said that although they believed Farrell the better actor, Schwarzenegger in the original was "more of a movie presence and better suited for the role".
After premiering at the Toronto International Film Festival, Seven Psychopaths (Farrell's second film with McDonagh) was released in October 2012. The actor starred as creatively blocked writer Marty in a black comedy with Sam Rockwell, Woody Harrelson and Christopher Walken. It broke even at the box office and reviews were generally good, with David Rooney of The Hollywood Reporter writing that Farrell "serves as an excellent foil for Rockwell" and the actor "is in subdued mode...his performance largely defined by the endless expressivity of his eyebrows". That month, Farrell appeared on the cover of the magazine Details.
March 2013 saw the release of Dead Man Down, a thriller directed by Niels Arden Oplev reuniting Farrell with Terrence Howard for the first time since Hart's War ten years earlier. Noomi Rapace, star of Oplev's The Girl with a Dragon Tattoo, starred as a facially scarred woman who blackmails Farrell's character into killing the man who disfigured her in a car crash. Reviews were mixed, with Empire calling the film "a pleasingly intricate double (or is it triple?) revenge plot anchored by excellent acting" and The Hollywood Reporter saying that "[J.H.] Wyman's script and the measured pace don't lend themselves to the necessary escalating tension that would have resulted in a more rewarding climax." The New York Times' Manola Dargis called the film a failure, but said of the actor: "Farrell and his sensitive, hardworking eyebrows help keep it from becoming a full-bore lampoon." Joe Neumaier of the New York Daily News also disliked the film; it contained "a lot to roll your eyes over" and, while Farrell was commendable, he was "as stoic as a statue".
In 2014, Farrell starred in a film adaptation of Mark Helprin's Winter's Tale. The film was written and directed by Akiva Goldsman and based on Helprin's 1983 novel, and co-starred Jessica Brown Findlay, Russell Crowe, and Will Smith. Farrell won the lead role over younger actors Garrett Hedlund, Tom Hiddleston and Aaron Taylor-Johnson. Although the film generally received negative reviews due to the overly romantic nature of the film, writers such as The Village Voice's Stephanie Zacharek had nothing but praise for Farrell. She described him as "an extraordinary appealing actor" who "has always made a terrific bad boy, but ... seems to be settling into some very serious, responsible-adult roles." Mick LaSalle of the San Francisco Chronicle agreed, writing that the actor "holds the movie together" and is part of "the most beautiful [love scene] so far of 2014."
His work as the alcoholic father that P.L. Travers adores in Saving Mr. Banks got contrasting reviews with Variety's Scott Foundras calling it "excellent" and Leslie Felperin of The Hollywood Reporter "his best work in some time" but The Guardian's Peter Bradshaw describing it as "bland" and "uninspired" and The Telegraph's Robbie Collin expressing that the actor was wrong for the role.
Farrell appeared in Liv Ullmann's adaptation of August Strindberg's Miss Julie with Jessica Chastain and Samantha Morton. His turn as John, the serving man to Chastain's character's father, was described by Stephen Holden of the New York Times as the "strongest" of the three performances, though Ullmann's direction was deemed too flat by most reviewers. He starred in the second season of HBO's True Detective as Ray Velcoro, alongside Vince Vaughn, Taylor Kitsch, and Rachel McAdams. The first two episodes were directed by Justin Lin. He worked with a dialect coach to get the nonstandard California accent for his character, which he found challenging.
Farrell starred in The Lobster, a romantic science fiction thriller which was released in 2015 and directed by Greek director Yorgos Lanthimos in his English-language debut. Its script was awarded the ARTE International Prize for Best CineMart 2013 Project at the 42nd Rotterdam International Film Festival. Set in a dystopian near-future in which finding a partner is a matter of life and death, the film tells an unconventional love story. The film also stars Rachel Weisz, Ben Whishaw, Olivia Colman, Léa Seydoux and John C. Reilly.
Farrell also appeared in the Harry Potter spin-off film Fantastic Beasts and Where to Find Them.
In 2017, Farrell starred in The Beguiled and The Killing of a Sacred Deer. He has also shot Roman J. Israel, Esq. (which will also be released in 2017), Widows, and Dumbo back to back to back with the latter two releasing in 2018 and 2019, respectively.
In 2007, Farrell joined other celebrities as a spokesman for the Special Olympics World Games in Shanghai, China. He has also lent his support to the anti-bullying campaign Stand Up! organised by the Irish LGBT youth organisation BeLonG To in March 2012. The actor appeared on The Ellen DeGeneres Show two years earlier to increase awareness of the subject. In 2015 Farrell became an official Ambassador of the Homeless World Cup which uses street football to inspire homeless people to change their lives.
Farrell met English actress and singer Amelia Warner at the premiere of Quills in 2000. They dated from July to November 2001. There was speculation that they married; of the experience, the actor said "Too fast, too young." However, in December 2011 Warner told The Sun that the marriage was never legal: "We had a ceremony on a beach in Tahiti that was by no means legal and we knew it wasn't... It was just a thing we did on holiday. We went shark feeding and then we did that. We booked them both on the activities desk at the hotel." Farrell has a tattoo of Amelia's name around his ring finger.
By the end of 2003 he was linked to singer Britney Spears, Playboy cover girl Nicole Narain, model Josie Maran and actresses Angelina Jolie, Maeve Quinlan and Demi Moore.
Farrell and Kim Bordenave became parents of a son (James Padraig), born in 2003, in Cedars-Sinai Medical Center, Los Angeles. In October 2007 he said his son has Angelman syndrome, a rare genetic disorder characterised by intellectual and developmental delay, lack of speech and a happy, excitable demeanor.
From 2007 to 2008 the actor dated Muireann McDonnell, an Irish medical student.
Farrell and British-American writer Emma Forrest dated for over a year, an experience she discusses in depth in her memoir Your Voice in My Head (focusing on her relationship with her therapist, who died unexpectedly); it is a planned film starring either Emily Blunt or Emma Watson, and Stanley Tucci, and directed by Francesca Gregorini. According to Forrest, she and Farrell planned to have a child together before he ended the relationship.
Farrell fathered his second child (Henry Tadeusz), a son born on 9 October 2009, with Polish actress Alicja Bachleda-Curuś. His relationship with Bachleda-Curuś ended in mid-2010.
On 5 July 2016, Farrell's father Eamon was married at the age of 73 to Eileen Pollard from Dublin. The ceremony took place in Limassol, Cyprus, with Farrell flying in for the event.
In December 2005, Farrell checked into a rehabilitation treatment centre for addictions to recreational drugs and painkillers. He spoke about it on the Late Show with David Letterman after coming out of rehab and continued to do so in the years following. "There was an energy that was created," he says of the time when he was addicted, "a character that was created, that no doubt benefited me. And then there was a stage where it all began to crumble around me."
On 20 July 2006, as Farrell was being interviewed by Jay Leno on The Tonight Show, telephone sex worker Dessarae Bradford evaded security, walked on stage, confronted Farrell, and threw a book on Leno's desk. As Farrell escorted her off the stage and handed her over to NBC security, she shouted "I'll see you in court!" After being held by the Burbank police, Bradford was released. The next day, Farrell obtained a restraining order against her and the incident was edited out of the broadcast.
Bradford had twice attempted to sue Farrell for abusive messages, but the lawsuits were dismissed due to a lack of evidence. She failed a lie detector test on an Ion Television programme when attempting to prove her claims.
In January 2006, Farrell filed a lawsuit against his former girlfriend, Playboy model Nicole Narain, and the Internet Commerce Group (ICG) for the unauthorised public distribution of a 13-minute sex tape which they made in 2003. He was offered $5 million for its rights. While ICG tried to release it, Narain said that she would work with Farrell to ensure that the tape remained private; Farrell said she tried to release it to damage his acting career and "make money out of it", a claim Narain denies. On 16 April 2006 they reached a confidential settlement; Farrell's lawsuit against ICG continued, with a trial date of 21 July 2006. Eventually, it was settled amicably.