Paolo Birro was born in 1962 in Noventa Vicentina, in the province of Vicenza. He trained first as a classical pianist, earning his piano diploma from the Conservatorio di Vicenza in 1987 under maestro Carlo Mazzoli with top marks, honors and special mention, before turning to the jazz that had drawn him since childhood. Two decades later, in 2007, he added a Level II advanced jazz diploma from the Conservatorio di Adria, again with highest marks and honors.

His breakthrough came in 1992, when a trio he formed with guitarist Sandro Gibellini and clarinetist Mauro Negri won first prize at the International Barga Jazz Competition; the three later documented the group on The Tender Trap (1997), Discogs-verified as a co-billed date. In 1996, critics polled by Musica Jazz named him Best New Talent in Italian jazz.

Birro built his own catalog through duo and small-group partnerships rather than a single working band. He made two co-led albums with tenor saxophonist Emanuele Cisi, Mayday (1997) and Hidden Songs (2002), both Discogs-verified piano-and-tenor duo dates. He recorded Autunno (2001) and Farfalle (2002, with Gil Goldstein) alongside saxophonist Pietro Tonolo, and joined bassist Ares Tavolazzi on Simone Guiducci's co-led My Secret Love (2002). He plays piano in Claudio Fasoli's working Gammatrio, appearing on Gammatrio (2002), Stilla (2003) and Episod (2005), all Discogs-verified, and has also recorded as the Claudio Fasoli - Paolo Birro Duo. As a leader in his own right he recorded the solo piano recital Capo D'Astro (1998, on a 1930 Steinway D once owned by Arthur Rubinstein), Spring Jazz Trio (2004) and Sbandio (2008).

Birro has been a member of Riccardo Brazzale's Lydian Sound Orchestra since the early 2000s, appearing on its albums from Monk At Town Hall & More (2002) through Mare 1519 (2019). On the orchestra's Azurka (2003), Discogs track-level credits place him on piano alongside Mauro Beggio on drums, with Fasoli as featured composer and soloist, connecting all three musicians on a single date. Birro and Beggio also co-led the working piano trio Radiotrio, with bassist Federico Malaman, on their 2014 album for Almarecords. He is Discogs-verified alongside Lee Konitz on the duo/trio session billed Lee Konitz Meets Paolo Birro Trio, and alongside saxophonist Michele Polga on Clouds Over Me (2009) and Little Magic (2015). A 2002 live-festival release, Rememberin' Bicio, credits a specific "Paolo Fresu & Paolo Birro" duo pairing alongside separate sets by other Italian musicians, connecting him to Paolo Fresu; Discogs also lists him among the credited musicians on Fresu's Cinquant'Anni Suonati - 3 (2012) anthology. He appears alongside Marcello Tonolo on the multi-pianist compilation Mystere Piano (2007).

Since 2015 Birro has anchored a long-running quartet with the American swing tenor saxophonist Scott Hamilton, bassist Aldo Zunino and drummer Alfred Kramer, recording a run of albums for the audiophile label Fone Jazz that runs from Bean And The Boys (2015) through Cinerama, Music From The Movies (2024), the last recorded live-to-disc at the Auditorium Museo Piaggio in Pontedera. According to his own biography, he has also performed with Buddy DeFranco, Art Farmer, Johnny Griffin and Enrico Rava, though none of these specific connections were independently confirmed at the Discogs credit level for this profile.

Alongside performing, Birro has taught jazz piano at the Conservatorio di Vicenza since 2003, and has also taught at the Civici Corsi di Jazz in Milan, the International Jazz Master Classes in Siena, and the jazz department of the Conservatorio di Bologna. With pianist Rossano Sportiello he co-authored the instructional volume Master in Piano Jazz, published by Ricordi, and he has written for the magazines Musica Oggi and JazzIt.

Birro works in a mainstream, standards-and-songbook idiom built on duo and small-group intimacy rather than a fixed working band: piano-and-horn duos with Emanuele Cisi and Pietro Tonolo, the swing-tenor quartet with Scott Hamilton, and a solo recital on Capo D'Astro. His touchstones sit inside the American songbook and film-music repertoire (Irving Berlin, Hoagy Carmichael, the Cinerama soundtrack program), and his long-standing membership in Riccardo Brazzale's Lydian Sound Orchestra and in Claudio Fasoli's Gammatrio places him inside two of the more established repertory and small-group projects in Italian jazz. The 1992 Barga prize, won as part of a trio with a guitarist and a clarinetist rather than a conventional rhythm section, points to an early preference for chamber-scaled, interplay-driven settings that has carried through his career.