Simon Holt was born in Bolton, Lancashire in 1958. After completing a foundation course at Bolton Art College, he went on to study composition with Anthony Gilbert at the Royal Northern College of Music in Manchester. He is a Fellow of the Royal Northern College of Music and of the University of Bolton. As a young composer he was commissioned by the artistic director of the London Sinfonietta, the late Michael Vyner. Kites was premièred by them at the Queen Elizabeth Hall, London in 1983. In 1985 Holt was featured composer of the Bath International Festival at which the late William Mann was the artistic director. Holt's relationship with the London Sinfonietta has continued with a steady stream of performances and premières, including Ballad of the Black Sorrow (1988), eco-pavan (1998) and Sueños (2006) for baritone and ensemble, performed by Roderick Williams and the London Sinfonietta conducted by Thierry Fischer in London and Madrid.

Simon Holt's output for chamber ensemble is large, including ten pieces written for the Nash Ensemble. The first four of these: Shadow Realm (1983), Era madrugada (1984), Canciones (1986) and Sparrow Night (1989) have been recorded by the Nash Ensemble on the NMC label. After the fifth piece, all fall down (1994), a sixth was commissioned for the 2004 Cheltenham Festival, namely the other side of silence (2004), followed by the string trio, 4 quarters (2005), and String Sextet: the torturer's horse (2009) and bagatelarañas (2010) for wind quintet, was premièred in March 2017 at Wigmore Hall. His most recent work for the Nash Ensemble is Cloud Shadow to be premièred in 2021. Holt has also developed a successful relationship with Birmingham Contemporary Music Group, who recorded a second portrait CD on the NMC label, released in 2004, featuring Kites, Lilith (1990), eco-pavan, Boots of Lead (2002) and feet of clay (2003). To date, Holt has been commissioned to write four major orchestral pieces for the BBC Proms. In 1987, John Drummond commissioned Syrensong for the BBC Symphony Orchestra, later followed by the viola concerto walking with the river's roar (1991), premièred by Nobuko Imai and the BBC Philharmonic in 1992. Latterly, Troubled Light (2008) and the flute concerto Morpheus Wakes (2014), for Emmanuel Pahud, were both premièred by the BBC National Orchestra of Wales, conducted by Thierry Fischer, during Holt’s fruitful tenure as Composer in Association at the BBC National Orchestra of Wales 2008 – 2014. Other works from this period include St Vitus in the kettle (2008), the double concerto for clarinet and flugelhorn, Centauromachy (2009) and The Yellow Wallpaper (2011), for soprano and orchestra. 

Holt has found inspiration in, amongst other things, the world of Greek myth. His cycle 3 for Icarus culminated in 1995 with the première of his cello concerto Daedalus Remembers (1995), commissioned by the Cheltenham Festival for Rohan de Saram and Sinfonia 21 conducted by Daniel Harding. In addition, he feels a great affinity for the writing of Federico Garcia Lorca whose dark, passionate and enigmatic texts have much in common with Holt's own sound world. He has set Lorca's texts in his song cycle Canciones and his first opera The Nightingale's to Blame (1996-8). This was a commission from Opera North, the Huddersfield Contemporary Music Festival, and the Munich Biennale, and the première formed the focal point of a major retrospective at the 1998 Huddersfield Contemporary Music Festival. Simon Holt's soprano and orchestra piece, Sunrise' yellow noise (2000) for the City of Birmingham Symphony Orchestra and Lisa Milne under Sir Simon Rattle went on to tour the Cologne Triennale in May 2000, and was the subject of a one-hour South Bank Show TV documentary.

In 2001, Simon Holt received Le Prix de la Fondation Prince Pierre, Monaco for this piece. Sunrise' yellow noise is the first part of the cycle, a ribbon of time, which encompasses five pieces of various forces based on poems by Emily Dickinson. The other four pieces are Two movements for string quartet (2001), which received the Royal Philharmonic Society Award in 2002; Boots of Lead for alto and ensemble, which was premièred by BCMG, Rinat Shaham and Sir Simon Rattle in October 2002 and received the Ivor Novello Classical Music Award; Clandestiny (2000) for soprano and organ; and startled Grass (2001) for female voices, cimbalom, harp and cello. The music theatre piece, Who put Bella in the Wych elm? (2003), commissioned by Aldeburgh Almeida Opera, was performed around the UK in 2003 to great acclaim and judged Best Stage Work at the 2004 British Composer Awards. It led to a further cycle of pieces: The sharp end of night (2005) for solo violin, the other side of silence for flute, viola and harp and The Coroner's Report (2004) for ensemble followed by Who put Bella in the Wych elm?.

Holt's large-scale pieces include the violin concerto, witness to a snow miracle (2005), premièred in London and then played in Bonn as part of the Beethoven Festival by Viviane Hagner and the BBC Symphony Orchestra, and judged Best Orchestral Work at the 2006 British Composer Awards; and a percussion concerto for Colin Currie entitled a table of noises (2007), which was premièred by the City of Birmingham Symphony Orchestra in May 2008 and also won the Orchestral Award at the British Composer Awards in 2009. These two concertos, along with the orchestral work St Vitus in the kettle, appear on the NMC CD recorded by the Hallé, conducted by Nicholas Collon, released in March 2017. Holt’s latest CD recording, also on NMC and released in May 2017, is of the 3rd Quartet (2013) in its world première performance by the JACK Quartet at the Wigmore Hall.

In autumn 2016, Holt’s piccolo concerto Fool is hurt (2015), co-commissioned by the London Sinfonietta with the NOVA Ensemble of Utah, received its première performances in Salt Lake City (with Caitlyn Valovick-Moore as soloist) and London (with Michael Cox as soloist). In summer 2017, the basset clarinet concerto Joy Beast (2016), written for Mark Simpson and commissioned by the BBC, was premièred in Hull and London as part of the New Music Biennial 2017, a PRS for Music Foundation initiative presented in partnership with Hull UK City of Culture 2017, London’s Southbank Centre and BBC Radio 3.

Holt’s latest orchestral piece Surcos (2016), co-commissioned by the Berliner Philharmoniker and the City of Birmingham Symphony Orchestra, received its world première performances in May 2017, in Berlin and Hamburg, conducted by Sir Simon Rattle; the UK première, conducted by Ilan Volkov, took place in Birmingham on June 13 2018.

Simon Holt celebrated his 60th birthday on 21 February 2018. To mark this occasion, the BBC National Orchestra of Wales performed the UK première of an icicle of moon (2014), alongside St Vitus in the kettle and the BBC Philharmonic presented a table of noises with Colin Currie at the Bridgewater Hall, Manchester (February 17). In June 2018, the Aldeburgh Festival featured Holt’s chamber music in three concerts, including two new commissions: Llanto (para las chumberas) (2017), for oboe d’amore and string trio (June 11) and 4th Quartet: Cloud House (2017), which was premièred by the Piatti Quartet (June 22).

Holt’s Quadriga for percussion and string quartet, written for Colin Currie and the JACK Quartet, was premièred as part of the BBC Proms 2018 season. This prom was chosen for rebroadcast for the 2020 Digital BBC Proms. Holt’s tenth commission for the Nash Ensemble, Cloud Shadow, received its première on 27 April 2021 in the Wigmore Hall. Psappha Ensemble premièred their 30th anniversary commission, The Sower, in Kettle’s Yard, Cambridge, on 17 February 2022 followed by two further performances in Sheffield and Manchester. Stephen Upshaw and Richard Uttley premièred Marsyas-Apollo in Cardiff University on 1 November 2022 and Kettle’s Yard on the 3rd.

'The Music of Simon Holt', edited by David Charlton - the first full-scale study of Holt's compositions - was published by Boydell & Brewer in September 2017.

Simon Holt is currently Professor of Composition at the Royal College of Music. The music of Simon Holt up to 2015 is published by Chester Music Limited. Since July 2016 Simon Holt has been self published.