The event celebrates independently-owned record stores, and will take place for its seventh year on April 19. The band plans to recognize the occasion with Unplugged: The Complete 1991 and 2001 Sessions, a new four-disc vinyl set that will become available on CD and online on May 20.
R.E.M. is the only band to headline MTV Unplugged twice, and the set will include complete versions of both concerts. Eleven unaired songs will also be included, five from the 1991 set and six from the 2001 show. Performances of tracks from 1998's Up and 2001's Reveal are part of the newly released material.
The band formed in 1980 in Athens, Georgia, and announced their breakup in September 2011.
"As R.E.M., and as lifelong friends and co-conspirators, we have decided to call it a day as a band," R.E.M. wrote on their website at the time. "We walk away with a great sense of gratitude, of finality, and of astonishment at all we have accomplished. To anyone who ever felt touched by our music, our deepest thanks for listening."
The band's last album, Collapse into Now, was released in 2011. Bandmates Bill Berry and Mike Mills performed together at guitarist Peter Buck's show last November, but Mills has stated to Rolling Stone that a full-on reunion is unlikely.
"We said we're done and we're done," Mills said with finality.
Mills will sign copies of the new set at Bull Moose record store in Scarborough, Maine on Record Store Day.