Martine Kimberley Sherrie Ponting was born on 14 May 1976 at the Salvation Army Mothers' Hospital in Hackney, London, to Jenny Ponting and Thomas "Keith" Hemmings. Whilst in a relationship with Keith, Jenny experienced domestic violence, which continued for many years after their split. After indefinitely leaving him at the age of 20, he continued to harrass Jenny and Martine. On one occasion, he threatened to drop Martine off the balcony if Jenny did not do as he asked; Martine describes this event as her first memory of her father. As a result they were forced to relocate frequently to escape from him, and they did so for four years. After one of many incidents, in which he attempted to kill both Jenny and Martine, he was arrested and later charged and remanded in custody for six months. However, as one of the witnesses disappeared and Jenny's brother died, and due to insufficient evidence, the charges were dropped and Keith was released from remand. Nevertheless, when Jenny met John McCutcheon, whom she later married, Keith stopped visiting them. When Martine was nine, Keith contacted Jenny and asked for access to Martine, which she didn't agree to, prompting him to seek sole custody through court. He eventually lost the case, and was also denied any access to Martine until she was 18 and told that he could not apply for it ever again due to his behavior in the past. Shortly after, her surname was changed to her stepfather's, McCutcheon. When Martine was sixteen, her mother gave birth to her half-brother, Laurence "LJ". Jenny and John eventually divorced, and Jenny married Alan Tomlin in 2000.
McCutcheon attended a nursery school in Colchester, Essex, and later the Shacklewell Infants' School in Hackeny, where she performed in her first play Away in a Manger, before progressing to the Shacklewell Juniors' at the age of six, where she appeared in more plays, including Noah's Ark. As she was getting more lead roles in plays at school, some of her peers began to bully her because of that. At the age of five, she began to attend extra dance classes, and later enrolled in a dance school in Stoke Newington. Shortly before her tenth birthday, she successfully auditioned for a place at the Italia Conti Academy of Theatre Arts. However, due to the changing policy of the Inner London Education Authority (ILEA) she was no longer eligible for the grant she was supposed to receive for coming second in the audition. She was therefore unable to pay her fees. As an alternative she began to attend Italia Conti's Saturday classes as her mother was only able to afford that. After her classes, she and her mother would go to the local library and search through books for trusts; they would get in touch with them to seek support in funding her place at Conti Italia. After many rejections, the Church of England charity based in Moorgate, the Reeves Foundation, offered Martine a grant, and she was able to enroll at the Italia Conti Academy of Theatre Arts. She finished the school with nine GCSEs.
At the age of 12, McCutcheon obtained her first acting role and was paid £350 to appear in an American television commercial for the drink Kool-Aid, which was followed by modelling assignments and bit parts in TV shows. She was given the part of Mandy in the TV series Bluebirds (1989) alongside Barbara Windsor, and also played Susan, Jane's sister (played by Denise van Outen), in the Anthony Newly directed production of Stop the World – I Want to Get Off, at the Churchill Theatre in Bromley, London, later tranferred to the West End Lyric Theatre in Shaftesbury Avenue. This followed with two guest appearances on the ITV police drama The Bill in 1991 and 1992, respectively. McCutcheon also appeared in the music video for the song "Caribbean Blue" by Irish singer Enya. By the time she was 15, she was part of an all-girl group, Milan, with two fellow pupils and landed a record contract with Polydor and a gig touring as the warm-up act for the British boyband, East 17. Milan were reasonably successful. Three of their singles: "Is It Love You're After", "Affectionately Mine" and "Lead Me On", charted in the top ten of the dance charts, with the latter also making it to the top 100 of the UK Singles Chart. However, they weren't successful enough to make a living and they disbanded.
In 1994, while working as a shopgirl at Knickerbox, McCutcheon was offered the role of Tiffany Raymond on the popular BBC soap opera EastEnders. McCutcheon took inspiration and advice from her mother on how to play the part. The role of Tiffany grew, as did McCutcheon's popularity, and 22 million viewers tuned in to see her final scenes in Albert Square in 1998 when her character was killed off in a special episode screened on New Year's Eve. For her portrayal of the character she received the 1997 National Television Award for Most Popular Actress and the 1998 TV Quick Award for Best Actress.
McCutcheon's first appearance on the charts occurred in 1995 on a minor dance song "Are You Man Enough" with the dance producers Uno Clio. A promotional video was also produced. In 1999, McCutcheon debuted as a solo pop artist with Virgin Records and scored a number 1 on the UK Singles Chart with the ballad "Perfect Moment" (originally recorded by Edyta Górniak in 1997). That same year she had two more top 10 entries, reaching number 6 with two singles: "I've Got You" and later with "Talking in Your Sleep", which featured the double A-side "Love Me", an album track that was re-recorded for the Children in Need appeal with all proceeds being donated to that cause. All three singles were taken from her debut album, You Me & Us, which peaked at number 2 on the UK Albums Chart and was certified platinum by the British Phonographic Industry (BPI).
In 2000, McCutcheon released her second album, Wishing, which was less successful, charting at number 25 in the UK. The album spawned two singles – the number 2 hit "I'm Over You" and the follow up song, a cover of the Donna Summer classic "On the Radio" which peaked at number 7. Despite peaking at only number 25, the album still managed to sell around 250,000 copies and received a gold certification from BPI. McCutcheon released her third album, Musicality, a Broadway influenced cover album, in 2002. It reached number 55 in the UK and was certified silver by BPI, however her pop career stalled when, due to poor sales, her recording contract was cancelled. Her 2CD best-of-album called The Collection was released in September 2012.
McCutcheon returned to music in 2017 with her fourth studio album, Lost and Found, released in August by BMG. Its lead single, "Say I'm Not Alone" was released on 30 May 2017. The album peaked at number 17 in the UK, becoming McCutcheon's highest-charting album since the release of You Me & Us.
Whilst still in EastEnders, McCutcheon appeared in her first pantomime, playing the title role in Cinderella, at the Marlowe Theatre in Canterbury, Kent. She appeared in ITV's The Knock as well as the British film Kiss Kiss (Bang Bang) in 2000. She went on to play Eliza Doolittle in My Fair Lady at the National Theatre in London. Despite missing many performances (citing health problems) and withdrawing nearly five months early from the production's transfer to the Theatre Royal, Drury Lane, she won Laurence Olivier Award for Best Actress in a Musical at the 2002 ceremony.
In 2002, McCutcheon presented the National Music Awards for ITV1 and in 2003 she featured in her only major film role. She appeared as tea-lady Natalie in the Richard Curtis romantic comedy Love Actually, where the British Prime Minister (played by Hugh Grant) falls in love with McCutcheon's character. The film received good reviews and was a box office success. McCutcheon went to America in the wake of the film's success, but a Hollywood career did not materialise. She did however, win MTV Movie Award for Best Trans-Atlantic Breakthrough Performer. She also won the Empire Award for Best Newcomer at the awards' 2004 ceremony.
In September 2005, she appeared in two episodes of hit BBC drama series Spooks. Screened on the UK television station ITV1 in December 2005, McCutcheon appeared in The English Harem, playing a woman in love with a Muslim man (Art Malik), who marries him despite knowing he already has two wives. That same year she presented and performed on ITV's entertainment programme, Moviemusic Mania. In 2007, McCutcheon was seen in two independent films, Withdrawal opposite Patrick Swayze and Jump!, as well as the Agatha Christie's Marple television series episode "At Bertram's Hotel". She was also a judge in the second series of ITV1's Soapstar Superstar. Her appearance on the show drew criticism, with reports alleging that she was becoming a hate figure for the contestants, who were said to have found her comments relentlessly critical and at times patronising. She performed in an Art Plus fundraising event at the Whitechapel Art Gallery opposite Natalie Press, Samantha Morton and Rhys Ifans and in January 2008 she starred alongside actor Jason Donovan, in the ITV soap Echo Beach as character Susan Penwarden.
In September 2016, McCutcheon was announced as a regular panellist on the ITV daytime show Loose Women, after making few guest appearances on the show earlier in the year.
McCutcheon released her autobiography, Who Does She Think She Is? in 2000, and in 2003 Martine McCutcheon: Behind the Scenes – A Personal Diary, was published by HarperCollins. McCutcheon was one of many celebrities that featured in a promotional film for London's successful bid for the 2012 Summer Olympics, in 2004. A fitness DVD, Martine McCutcheon: Dance Body, was released in December 2005.
In August 2006, the supermarket chain, Tesco, announced that they would be using McCutcheon in a series of adverts to promote a new green scheme for recycling used plastic carrier bags. In 2009, she had her first novel, The Mistress, published by Pan MacMillan. In January 2010, she became the face on Danone's UK advertising campaign for its Activia yogurt brand.
McCutcheon was engaged to DJ Gareth Cooke, but broke off the relationship in 1996. She was also in a relationship with Jonathan Barnham, with whom she fell pregnant in 1999, however miscarried. McCutcheon married singer Jack McManus at Lake Como in September 2012. The couple had been dating since 2009. On 4 February 2015, she gave birth to a son, Rafferty Jack McManus.
In July 2014, she was awarded an Honorary Degree by the University of Bolton for her services to entertainment.