The following list was supplied by Bösendorfer. (Some, annotated here, were written for Bösendorfer but do not employ the extra notes.)
Béla Bartók
Piano concerto no. 2
Piano concerto no. 3 (88-note keyboard)
William Bolcom
Twelve new etudes. Scène d'opéra
Ferruccio Busoni
Various original compositions
Various J.S. Bach transcriptions
Claude Debussy
La Cathédrale engloutie (88-note keyboard)
Ernst von Dohnányi
Piano concerto (written for the occasion of the first Bösendorfer Competition in 1889)
Edward MacDowell
Eroica sonata
Frank Martin
Piano concerto no. 2
Modest Mussorgsky
Pictures at an exhibition. The Great Gate of Kiev (88-note keyboard)
Maurice Ravel
Jeux d'eaux (88-note keyboard)
Miroirs
Gaspard de la nuit. Scarbo (88-note keyboard)
Roger Sessions
Piano sonatas no. 2
Ralph Vaughan Williams
Various compositions
Richard Wagner
Parsifal (to supplement the bells, in the Vienna Philharmonic's scoring)