Barry Mills was born in Plymouth in 1949 and is for the most part self-taught as a composer. He obtained a degree in Biochemistry from Sussex University in 1971, returning there in 1976-77 to pursue an MA in Music, studying analysis with David Osmond-Smith and David Roberts and composition with Colin Matthews and Ann Boyd.

He is now retired after having been a postman for many years, a job which allowed him to compose in the afternoons.

Four CDs of his chamber music have been issued by Claudio Records. Thalia Myers commissioned the piano piece "Clouds" from him for the Spectrum 2 collection published by the Associated Board and recorded by her on the NMC double CD "Spectrum". This piece was issued by the Associated Board as a Grade 3 set piece in August 2002.

His orchestral piece "Tartano" was premiered by the Moravian Philharmonic Orchestra, conductor Jiri Mikula, in 1997 in Olomouc, the Czech Republic, and recorded by them for the Vienna Modern Masters label.

In addition to those musicians who have recorded Barry Mills' music on CD, his music has also been performed by: Philippa Davis, Michael Finnissy, Adam Swayne, Jacob Swindells, Terence Allbright, Richard Deering, Renee Reznek, Marianne Mezger, Jill Kemp/Rianka Bouwmeester, Charlotte Pugh, Robert Hinchcliffe, Rachel Fryer, Marcia Bellamy, Ian Glen, The Ridgewood Piano Duo (David Elwin and Dorothy Maxwell), Birgit Schwab/Daniel Ahlert (mandolin and guitar duo, Germany), Nancy Ruffer/Helen Crayford, Rattenbury/Jenner guitar duo, Jeux, Jane's Minstrels, Endymion Ensemble, Sounds Positive, Tacet Ensemble, Aulos Ensemble, Kevin Allen/Glen Capra (piano duo), Ensemble Amei, Vega Wind Quintet, London Myriad Ensemble, the California Consort, Esprit, Quintetto Auletico (Wind Quintet made up of members of the Swiss Italian Radio Orchestra), the Northern Saxophone Quartet, Singelee Saxophone Quartet (Italy), Quartetto di Sassofoni Arte (Switzerland), Hilser Trio, The Kingfisher String Quartet, Aurora Trio, Music4Cello, The Mercury Quartet, The Regency Ensemble, Trio Taffanel, The Shellira String Quartet, Brighton Youth Choir, Brighton Chamber Choir and Chamber Orchestra, Southern Winds, The Musicians of All Saints, the Akademisches Orchester Basel, conductor Raphael Immoos.

The Society for the Promotion of New Music have performed three of his pieces: Harp Sketches, Clarinet Quintet and Septet and shortlisted Four Preludes for String Orchestra and Tapestry for full orchestra. His music has been performed and broadcast in England (at many London venues, including the Wigmore Hall, Purcell Room, St Martin's in the Fields, St John's Smith Square, the Almeida Theatre and the Warehouse) and Switzerland. Performances have also taken place in the USA, Germany, Czech Republic and Italy.