Nikki Iles (born 16 May 1963) is an English jazz composer and musician, playing piano and accordion.
Iles was born in Dunstable, Bedfordshire, her parents both musicians (her father a drummer and her mother a pianist). She started her musical education at primary school, where she learnt to play the harmonica and the clarinet, and at eleven years old she won a junior exhibition at the Royal Academy of Music, where she studied clarinet and piano (1974–1981). She became a member of the Bedfordshire Youth Jazz Orchestra. As a result of her increasing involvement with jazz, she went on to the Leeds College of Music to study alto saxophone and piano (1981–1984).
She joined former husband Richard Iles' group Emanon (R. Iles trumpet, Mike Walker guitar, Iain Dixon saxophone). The members were also all founder members of the Creative Jazz Orchestra, alongside Vince Mendoza, Anthony Braxton, Mike Gibbs, Kenny Wheeler and Mark Anthony Turnage. Iles also began playing with several London-based bands, such as Steve Argüelles' group, Mick Hutton's Straight Face, Stan Sulzmann's quartet, and Tina May.
Iles won the 1996 John Dankworth Special Award at the BT Jazz Festival.
Iles is senior lecturer at Middlesex University, and has taught at the University of York, Leeds College of Music, the Guildhall School of Music, and in Bulgaria, Holland, France, and Finland. She also runs training workshops for the Associated Board (Jazz syllabus and is a tutor for the National Youth Jazz Collective.