The trek will launch January 15 at the Paramount Theatre in Denver and stop at performing arts centers and theatres through March.
MacMaster and Osborne will appear with the band through February 4.
After a short break, the tour will head back on the road through March 17 where they will close out the trek at Carnegie Hall in New York City.
The Chieftains are one of the best-known acts playing traditional Irish music today. They’ll be out promoting their upcoming release, Water From The Well, expected to reach shelves in February.
They have two certified gold records to their credit: 1991’s Bells of Dublin and 1995’s The Long Black Veil, which featured guest vocalists such as Mick Jagger, Sting, Sinead O’Connor and Marianne Faithfull.
MacMaster, whose cousin is Canadian bad boy Ashley MacIsaac, tours relentlessly in the U.S. and Canada. Her most recently recorded album, In My Hands, was released in 1999 but a previous disc, My Roots Are Showing, was released in the U.S. in 2000.
The album has been nominated for a Grammy Award this year in the best traditional folk category.
Osborne, best known for her 1995 hit album Relish and single “One of Us,” released Precious Love, her first record in five years, last September.