Stefano Battaglia was born in Milan on 31 August 1965 and started piano at seven. He came up through the Conservatory of Milan on the baroque keyboard repertoire, Bach, Scarlatti and Handel, and on the twentieth-century composers he still names, Hindemith, Messiaen, Boulez and Ligeti. He first appeared on the European festival circuit as a classical player. In 1986 the J.S. Bach Festival in Dusseldorf named him best new pianist of the year. Eleven years later, in 1997, Brussels National Radio named him best young European pianist. Italy's Musica Jazz named him best new talent in 1988 and best Italian musician in 1999.

His leader debut, Things Ain't What They Used To Be, was recorded at the Barigozzi Studio in Milan on 22 and 23 June 1987, with Piero Leveratto on double bass and Gianni Cazzola on drums, and released on Splasc(h). Auryn followed in 1988 with Paolino Dalla Porta on bass and Manhu Roche on drums. Dalla Porta became the constant of his first fifteen years on record, appearing on nine of his albums between 1988 and 2000.

The classical training did not get traded away, and the clearest evidence is a pair of records. In December 1992 Battaglia recorded Bill Evans Compositions Vol. 1 with Dalla Porta and the drummer Aldo Romano, and in December 1993 he made a second volume with the same trio. Numbered volumes surveying one composer's catalogue is what a classical pianist does with Scarlatti sonatas, and Battaglia applied the form to a jazz writer. He did it again with the wider repertory at the turn of the century: The Book Of Jazz Volume One, recorded at the Teatro dei Rozzi in Siena in May 2000, and Volume Two, taped in the same room in September 2001, both with Dalla Porta and Fabrizio Sferra.

Between 1990 and 1998 he worked in four unrelated formats. Explore (1990) is a piano and drums duo with the English free improviser Tony Oxley, recorded at Barigozzi on 11 February 1990; the two returned with Dalla Porta for Sulphur in 1995. Baptism and Life Of A Petal are solo piano records, both cut at MUREC Studio in Milan on 5 December 1993. Fiabe (EGEA, 1995) is a clarinet and piano duo with Gabriele Mirabassi. And in June 1997, at the Spazi Sonori Studio in Livorno, he assembled Stefano Battaglia Theatrum, a fourteen-piece ensemble of saxophones, clarinets, trumpet, three basses and three drummers, and recorded enough material for three albums: Gesti and Mut(e)azioni I-XV in 1998 and Rito Stagionale in 2000.

Three days in Zurich in December 1997 produced five more records. Battaglia went into the Radio DRS 2 studios and taped solo material, a trumpet duo with Michael Gassmann, a percussion duo with Pierre Favre, and a trio with both. Splasc(h) released the results as Ecumenica, Musica Centripeta, Inner Book, When We Were and Omen, and they were later reissued as The Swiss Radio Tapes, volumes 1 through 5.

Manfred Eicher signed him to ECM in 2003. Raccolto, recorded that September and December at the Artesuono studio in Udine, came out in 2005 as a double album with Michele Rabbia on percussion, Giovanni Maier on double bass and Dominique Pifarely on violin. It was the first of seven ECM releases.

Re: Pasolini followed in 2007 (ECM 1998/99), recorded in 2005 and produced by Eicher and Battaglia together. The double album is built on Pier Paolo Pasolini. Disc one is a trio with Salvatore Maiore on double bass and Roberto Dani on drums; disc two opens into a larger group with Pifarely on violin, Vincent Courtois and Aya Shimura on cello, Bruno Chevillon on double bass, Gassmann on trumpet, Mirco Mariottini on clarinets and Rabbia on percussion. The composer credits run to Pasolini himself and to Domenico Modugno alongside Battaglia's own writing.

The Maiore and Dani trio then held for three albums: The River Of Anyder (ECM 2151, recorded November 2009 at the Auditorio RSI in Lugano), Songways (ECM 2286, Lugano, April 2012) and In The Morning, a reading of the American songwriter Alec Wilder taped live at the Teatro Vittoria in Turin on 28 April 2014 during the Torino Jazz Festival. Pastorale (ECM 2120, 2010) sits alongside them as a duo with Rabbia on percussion and electronics, with Battaglia on piano and prepared piano.

Pelagos (ECM 2570/71, released 15 September 2017) is the solo record. It was made in May 2016 at the Fazioli Concert Hall in Sacile in two sessions on a single day, one behind closed doors and one before an audience, on piano and prepared piano. Battaglia has said he spent the two days beforehand in a monastery thinking about migration. Seventeen tracks across two discs carry titles including "Migralia," "Halap" and "Dogon," and the programme includes two readings of the Arabic traditional song "Lamma Bada Yatathanna."

Teaching has run in parallel with all of it. Battaglia has given master classes at Siena Jazz every summer since 1988 and has led Siena's Laboratorio Permanente di Ricerca Musicale, a standing workshop on improvisation, composition and musical research, since 1996. Since 2018 he has taught at the Accademia Musicale Chigiana, where he conceived and directs Tabula Rasa, an improvisation ensemble formed jointly by Chigiana and Siena Jazz. Three Tabula Rasa albums appeared on the Centripeta label in 2025.

He is still recording steadily. Since 2019 he has made three duo albums with the Friulian singer Elsa Martin: Sfueai (Artesuono, 2019), Al centro delle cose (2020) and LYRA (Altrisuoni, 2025), the last of them set to Pasolini's lyrics and dedicated to him, returning to the subject of Re: Pasolini eighteen years later. The solo record Musica Salva arrived on 10 October 2025, and Prayers for Palestine, a duo with the Turkish saxophonist Tamer Temel, on 28 November 2025. On 19 February 2026 the Stefano Battaglia Standards Quartet released One Mile Away on Emme Record Label.

Battaglia's first vocabulary was the baroque keyboard repertoire, and the habits it left are audible: a preference for line over chord voicing, an interest in variation form, and a willingness to treat a body of compositions as a subject to be worked through rather than a set of vehicles. ECM's own account of him names Paul Bley and Keith Jarrett as the players who first pulled him toward improvised music, and the influence shows less in phrasing than in the assumption that a piano record can be built out of nothing but the moment.

He works consistently in two directions at once. One is compositional and thematic: records organised around an outside subject, as Re: Pasolini is around a poet and filmmaker, Pelagos around the Mediterranean, and In The Morning around Alec Wilder's songbook. The other is free and textural, running through the Oxley and Favre duos, the Theatrum ensemble writing, and the long partnership with percussionist Michele Rabbia, where prepared piano and electronics blur the instrument's edges. Pelagos holds both at once, since Battaglia plays piano and prepared piano across the same programme.

His own stated aim is to simplify, and to treat music as what he calls a universal metalanguage, a place genuinely without boundaries. That is the clearest explanation for a catalogue that moves from Bill Evans's tunes to a fourteen-piece free ensemble to an Arabic muwashshah without changing players' hands.