Lill studied at the Royal College of Music and with Wilhelm Kempff. His talent emerged at an early age, and he gave his first piano recital at the age of nine. At age 18, he performed Rachmaninoff's 3rd Piano Concerto under Sir Adrian Boult. This was followed by his much-acclaimed 1963 London debut playing Ludwig van Beethoven's Piano Concerto No. 5 at the Royal Festival Hall. In 1970 he won the Moscow International Tchaikovsky Competition (ex-aequo with Vladimir Krainev). It was said by Sidney Harrison that "he (John Lill) simply devours Beethoven. I set him work for the week - he does that and more."
Lill has performed in over fifty countries, both as a recitalist and as a concerto soloist. He has worked in the major European concert cities, including Amsterdam, Berlin, Paris, Prague, Rome, Stockholm and Vienna, as well as in Russia, the Far East and Australasia (including several Australian Broadcasting Corporation tours). He has also performed in the United States with the Symphony Orchestras of Cleveland, New York, Philadelphia, Dallas, Seattle, Baltimore, Boston, Washington, D.C. and San Diego.
His repertoire includes more than seventy concertos, and he is acclaimed in particular as a leading interpreter of Beethoven, whose complete sonata cycle he has performed on several occasions in the UK, US and Japan. In Britain, he has given over 30 BBC Promenade concerts and regularly appears with all the major Symphony Orchestras. He has toured overseas with the London Symphony, London Philharmonic, BBC Symphony, CBSO, Hallé, Royal Scottish National and BBC Scottish Symphony Orchestras.
Lill has recorded for Deutsche Grammophon, EMI (Complete Beethoven Piano Concertos with RSNO and Gibson), ASV (both Brahms Concertos with the Hallé and Loughran) plus the complete Beethoven Sonatas and Tchaikovsky l with the LSO and Judd. More recently, he has recorded the complete Prokofiev sonatas with ASV and his recent recording of the complete Beethoven Bagatelles and Piano Concertos with the CBSO and Weller is available on Chandos. He recorded Malcolm Arnold's Fantasy on a Theme of John Field (dedicated to John Lill) with the Royal Philharmonic Orchestra and Vernon Handley for Conifer. He has also recorded the complete Rachmaninoff Concertos and major solo piano works for Nimbus Records. His most recent recording projects have been the 60th birthday release of piano works by Schumann on the Classics for Pleasure label and new releases for Signum records of Schumann, Brahms and Haydn.
- Hilary Finch, "Urbane space man'. The Times, 27 February 2004.
- Fiachra Gibbons, "Robbers slash pianist's hands". The Guardian, 2 August 2000.
- Sandra Laville, "Muggers attack pianist who played for Queen Mother". Telegraph, 2 August 2000.
- Stephen Moss, "Play on". The Guardian, 4 August 2000.
- Tom Lappin, "Classical master's birthday treats". The Times, 28 March 2004.