The last movement, marked Alla turca, popularly known as the "Turkish Rondo" or "Turkish March", is often heard on its own and is one of Mozart's best-known piano pieces. Mozart himself titled the rondo "Alla turca". It imitates the sound of Turkish Janissary bands, the music of which was much in vogue at that time. Various other works of the time imitate this Turkish style, including Mozart's own opera Die Entführung aus dem Serail. In Mozart's time, the last movement was sometimes performed on pianos built with a "Turkish stop", allowing it to be embellished with extra percussion effects.
The third movement is a rondo in the form A–B–C–D–E–C–A–B–C–coda, with each section (except the coda) being repeated.
- Section A: This section, in A minor, consists of a rising sixteenth-note melody followed by a falling eighth note melody over a staccato eighth-note accompaniment. It is eight measures long.
- Section B: This section introduces new material in a melody in thirds and eighth notes before varying the A section with a crescendo before falling back to piano.
- Section C: A forte march in octaves over an arpeggiated chord accompaniment. The key changes to A major.
- Section D: A piano continuous sixteenth note melody over a broken-chord accompaniment. This section is in F♯ minor.
- Section E: A forte scale-like theme followed by a modification of section D.
- Coda: A forte theme consisting mostly of chords (arpeggiated and not) and octaves. There is a brief piano restatement of the theme in the middle of the coda. The movement ends with alternating A and C♯ octaves followed by two A-major chords.