The baritone horn, or simply baritone, is a member of the brass instrument family.[1] The baritone horn is a Cylindrical bore instrument like the trumpet and trombone. [2] A baritone horn uses a large mouthpiece much like those of a trombone or euphonium. It is pitched in B♭, one octave below the B♭ trumpet. In the UK the baritone is frequently found in brass bands. The baritone horn is also a common instrument in high school and college bands.

The baritone is pitched in concert B♭, meaning that when no valves are in use the instrument will produce partials of the B♭ harmonic series. Music for the baritone horn can be written on both the bass clef and the treble clef. When reading from the bass clef, the baritone horn is a non-transposing instrument. However, when reading from the treble clef, it can become a transposing instrument, where the C on the horn is the concert B♭, with the fingerings matching those of the trumpet or can continue to be played as a non-transposing instrument by continuing to play the same fingerings as played in the lower octave.

The baritone is part of the low brass section of the band.