The Boston Celtic Music Festival (BCMFest) is a 23-year-old celebration of Celtic music traditions presented by Passim, a Cambridge-based nonprofit supporting vibrant music communities. The festival returns to venues across Cambridge and Somerville including Club Passim, Crystal Ballroom, The Burren, The Rockwell, Arts at the Armory, and Somerville Theatre. BCMFest showcases the rich traditions of Celtic music, song, and dance from Greater Boston's Irish, Scottish, Cape Breton, Quebecois, and other Celtic communities.

The festival presents "everything from traditional tunes to contemporary Celtic sounds, featuring both professional touring acts and beloved local session musicians — highlighting artists across generations." The 2026 edition features headliners Altan and Old Blind Dogs, with Passim's Brian O'Donovan Fund recipient Scottish Fish also performing prominently. The festival spans four days (January 15-18) with multiple event formats designed to showcase different performance styles and encourage participation.

Programming includes First Round showcases of traditional sounds at Club Passim, the Boston Urban Ceilidh offering participatory social dances at Crystal Ballroom, Roots & Branches presenting dynamic contemporary-rooted styles, Old Blind Dogs performing at Arts at the Armory with local collaborators, and a Dayfest offering six hours of diverse Celtic music across three Davis Square venues. The festival culminates with Ireland's legendary Altan at Somerville Theatre, featuring a tribute to Brian O'Donovan.

Sunday workshops at Club Passim include Celtic Chorus group harmony singing, Fiddle Time instruction, and trad guitar accompaniment technique. The festival celebrates Greater Boston's deep cultural heritage in Celtic traditions while supporting local artists and the broader music community.