She began writing for the Soul Purpose magazine at age fifteen and was later made editor in 2002. She gave up her job as editor shortly after moving to Auckland in late 2002 in order to pursue her music career. In 2002, at the age of 18, Fraser signed a multi album deal with Sony Music, after a fierce bidding war between labels.

Fraser’s first album, What to Do with Daylight, was released in New Zealand in late 2003, which debuted at No. 1 and achieved gold status in the same week. The album eventually went seven times platinum, which sold over 105,000 copies in New Zealand alone. It remained on the album charts for sixty-six weeks. All five singles from the album reached the top twenty in the New Zealand Singles Chart. Her album also topped the New Zealand Top 50 Albums for all of 2004. The album also achieved gold status in Australia.

After the success of her first album, Fraser moved to Sydney in 2004. On 17 March 2008, she married Scott Ligertwood, in Sydney. “Brooke Fraser” has remained her stage name for her solo career.

In 2005, prior to writing and preparing her follow-up album, Fraser went to Rwanda before visiting her World Vision sponsor children in Tanzania. Fraser wrote the song “Albertine” about a young genocide victim (named Albertine), whom she met while in Rwanda. This song became her second album’s title track. For this album, Fraser decided to enlist a new band of American session musicians who had worked with an array of notable artists, both live and recorded.

Fraser has worked with World Vision as an Artist Associate since 2001. She has visited Cambodia and Tanzania with World Vision, the Philippines with Opportunity International and independently travelled to Rwanda in June 2005, in June 2006 as part of charity event “Hope Rwanda”, and in May 2007 when she filmed the music video for the song “Albertine” off her second studio album of the same name. Fraser was one of many New Zealand performers to work alongside New Zealand comedy band Flight of the Conchords in their 2012 New Zealand Red Nose Day charity song “Feel Inside (And Stuff Like That)”.

In 2006, Fraser and the band went into the studio in Los Angeles to record the album with producer Marshall Altman. The first single, “Deciphering Me”, reached No. 4 in the New Zealand single charts in 2006. On 4 December 2006, the album, Albertine, was released in New Zealand, which achieved double platinum status less than a month after its release. The album was released in Australia and internationally on 31 March 2007. In Australia, it charted at No. 29 in its first week on 9 April and has achieved Gold sales status. Albertine also became Fraser’s US debut, released on 27 May 2008. It entered the Billboard 200 at No. 90 on 19 July 2008. The album was propelled by online sales after being chosen as Editor’s Choice on iTunes. In 2008, Fraser undertook a major world tour, culminating the Montreal Jazz Festival and the Shepherd’s Bush Empire in London, UK. “Albertine” (the single) won the prestigious APRA Silver Scroll for Song of the Year in 2007.

Already part of Hillsong Church since 2005, Fraser joined the Australian church’s worship band—Hillsong Worship—where she participates under her married name: Brooke Ligertwood. The first album she was included on was the 2006 album Mighty to Save, on which she co-wrote “None But Jesus” from United We Stand, released in 2006. Her last live album with the band was the 2010 album A Beautiful Exchange, after which Fraser left Hillsong Worship. The 2016 live album Let There Be Light marked Fraser’s return and her first live recording with Hillsong Worship since her departure in 2010. She co-wrote and sang lead vocals on the song “What a Beautiful Name” for the 2016 live album. At the 2018 Grammy Awards, the group won the Best Contemporary Christian Music Performance/Song award for “What a Beautiful Name”. Billboard ranked the song as the top Christian Song of 2017 and third of the 2010s decade.

Flags was recorded at East West Studios in Hollywood in mid 2010 and released on 12 October 2010, in New Zealand, Australia and North America. Fraser celebrated with sold-out tours in all territories. Flags reached No. 1 on the New Zealand album chart, No. 3 in Australia and entered at No. 59 on the Billboard 200 in the US. Flags has been certified Gold in Australia and 3x Platinum in New Zealand, where it was also the sixth-highest-selling album of 2010. The first single, “Something in the Water”, achieved extensive radio success across the globe; it notably received BBC Radio 2 A-list rotation in the top 10 in Germany, Austria, Switzerland, Italy, Finland and Belgium and is a gold single in Germany and Italy. The single achieved double platinum sales in NZ where it spent 21 weeks in the 2010 singles chart. Flags was released in July 2011 in Europe and debuted in the album charts at No. 6 in Germany, No. 33 in Austria and No. 24 in Switzerland. A month after its release, Flags remained in the German top twenty at No. 13 and “Something in the Water” on the singles charts at No. 8. Flags was released in October 2011 in Hungary and reached No. 15 on the national album chart by the second week of release. Flags was later released in Sweden, Norway, Denmark and Finland on 7 November 2011.

In late 2010 whilst on tour in the US promoting her third album Flags, Fraser, in conjunction with charity: water, ran a birthday campaign asking her fans to donate $27 in honour of her 27th birthday. The goal was to raise $50,000 to build clean water wells in Ethiopia. The campaign was similar to those of Justin Bieber, Will Smith and Adam Lambert.

After the release of Flags, Fraser signed a recording contract with Vagrant Records and started recording her fourth studio album. On 13 August 2014, Fraser released a “taster track” titled “Psychosocial” on SoundCloud. The song marked a shift in musical direction for Fraser, as she moved from more acoustic and singer-songwriter based tunes to more electronic sounds. Her single “Kings and Queens” went to radio on 22 September 2014 and was available for digital download on 26 September 2014. On 1 October, she announced her fourth studio album, Brutal Romantic, would follow in November. The album was released in Australia, New Zealand and South East Asia on 14 November 2014 and in North America on 17 November 2014. The album was produced by Fraser and David Kosten, except the track “Magical Machine” which was produced by Fraser, Kosten and Dan Wilson. In September 2015, Fraser performed a song titled “Team, Ball, Player, Thing” as a part of a charity supergroup #KiwisCureBatten. It was an official supporters’ song of the All Blacks in the 2015 Rugby World Cup. It was also in aid of research into Batten disease via the New Zealand charity Cure Kids. It was released as a single on 11 September 2015. The day after it was released, the single debuted at No. 6 on the New Zealand Top 40 chart.

In March 2015, Fraser announced she was pregnant with their first child. A daughter was born on 18 September 2015. Fraser currently lives in Los Angeles, where she is occasionally on the Sunday worship team at the Hillsong Church Los Angeles campus. Another daughter was born on 10 July 2017.

In 2016, she released “Therapy”, off her first compilation album, A Sides, which was released 25 November 2016. This was followed by her second compilation album, B Sides, on 16 November 2018.