Bain was born in the town of Lerwick, in the Shetland Islands of Scotland. In the early years of his career, he was—briefly and unofficially—part of the band The Humblebums with Gerry Rafferty, Billy Connolly and Tam Harvey. He was one of the members of the band "Gordon Hank and the Country Ramblers", which also included Gordon Smith, Ian Stewart and Jack Robertson in 1967 and was based in Shetland. He became nationally prominent as a founding member of The Boys of the Lough, a Scots-Irish folk group, with whom he played for over 30 years. Simultaneously, Bain pursued a solo career in collaborative and television projects with Pelicula Films director Mike Alexander and producer Douglas Eadie, working on several international television series: The Down home Recordings, The Shetland Sessions, Aly Meets The Cajuns, and six series of the Transatlantic Sessions. Since the early eighties, Bain has regularly collaborated and recorded with prominent, international musicians, including: Phil Cunningham, Jerry Douglas, Emmylou Harris, Mark O'Connor, Jay Ungar, Mary Black, Mairéad Ní Mhaonaigh, Dan Tyminski, Rosanne Cash, James Taylor, Eddi Reader, Paul Brady, Darrell Scott, Michael Doucet, Martha Wainwright, Kate & Anna McGarrigle, John Martyn, Danny Thompson, Iris DeMent, Karen Matheson, Karan Casey, Donal Lunny, Joan Osborne, Allison Moorer, Bruce Molsky and Allan MacDonald, bringing traditional music to a wider audience. In 1989, Bain played at the Carnegie Hall in New York, USA, to a capacity crowd. In 1993, his autobiographyFiddler on the Loose, co-written with Alastair Clark, was published by "Mainstream". In 1999 Bain played at the first opening of the Scottish Parliament in Edinburgh. In 2000, Bain played at the funeral of the Scottish first minister Donald Dewar. In 2006, a television programme celebrating Bain's 60th birthday was broadcast by the BBC, documenting his life and works. The same year, Bain was inducted into the Scots Traditional Music Hall of Fame. In 2009, Bain collaborated with Nicola Benedetti to create a television programme for BBC Scotland: When Nicola Benedetti Met Aly Bain, broadcast the same year. In 2010, Bain made a further hour-long television programme for BBC with Pelicula Films and Billy Connolly: Fishing for Poetry, celebrating the life and works of the Scottish Poet Norman MacCaig. In 2012, Bain and Cunningham celebrated their 25th anniversary of touring as a fiddle and accordion duo. Bain also tours with Swedish multi-instrumentalist Ale Möller and with American old-time fiddler, singer, guitarist and banjo player Bruce Molsky; as a trio, they released their first album in 2013.
Bain has three daughters - Annalese, Jessica and Sophie who were respectively 25, 24 and 8 years old in 2003. He endorsed the independence campaign in the Scottish independence referendum, 2014.
In 2009 Paidriag O'Keefe's/Con Cassidy's from In The Tradition was included in Topic Records 70 year anniversary boxed set Three Score and Ten as track fourteen on the third CD.
With Tom Anderson
The Silver Bow
In 2009 Soldier's Joy from The Silver Bow was also included in Three Score and Ten as track seven on the fourth CD.
With Phil Cunningham
The Pearl
The Ruby
Another Gem
Spring the Summer Long
Best of Aly and Phil Volume One
Roads Not Travelled
Portrait
Five and Twenty
Best of Aly and Phil Volume Two
With Ale Möller
Fully Rigged
Beyond the Stacks
Meeting Point Aly Bain, Ale Moller and Bruce Molsky
