|Relative key||D-flat major|
|Parallel key||B-flat major|
|Dominant key||F minor|
|B♭, C, D♭, E♭, F, G♭, A♭|
B-flat minor is a minor scale based on B♭, consisting of the pitches B♭, C, D♭, E♭, F, G♭, and A♭. Its key signature has five flats. Its relative major is D-flat major and its parallel major is B-flat major. Its enharmonic equivalent, A-sharp minor, which would contain seven sharps, is not normally used.
The B-flat natural minor scale is:
Changes needed for the melodic and harmonic versions of the scale are written in with accidentals as necessary. The B-flat harmonic minor and melodic minor scales are:
B-flat minor is traditionally a 'dark' key. Important oboe solos in this key in the orchestral literature include the second movement of Pyotr Ilyich Tchaikovsky's Symphony No. 4, which depicts "the feeling that you get when you are all alone" in Tchaikovsky's words. Tchaikovsky's Piano Concerto No. 1 is also in B-flat minor. An Alpine Symphony by Richard Strauss begins and ends in B-flat minor.
The old valveless horn was barely capable of playing in B-flat minor; the only example found in 18th-century music is a modulation that occurs in the first minuet of Franz Krommer's Concertino in D major, Op. 80.
Samuel Barber wrote Adagio for Strings in B-flat minor as well.
See also: List of symphonies in B-flat minor