Although Chopin was essentially a miniaturist, he handled the sonata form with remarkable assurance. To a degree, his fairly hefty ballades, scherzos, and impromptus provided good preparation for writing the four movements of his third and final piano sonata, but this work's first movement, in particular, displays compositional skills that Chopin had few other opportunities to practice.

The first movement, Allegro maestoso, falls into traditional sonata form, constructed from a decisive and sometimes impulsive first theme and a more extended second theme, highly lyrical with a detailed accompanimental filigree -- music that would not be out of place in Chopin's nocturnes. The musical texture thickens considerably in the central development section; Chopin devotes long passages to variants on the second subject, but much of the development is highly contrapuntal. Following the recapitulation, which again emphasizes the second subject, the movement ends with a surprisingly peaceful coda.

The very brief Scherzo, molto vivace, uses light, fleet, but finger-challenging E flat outer sections to frame a gentle and pensive trio section in B major. The ensuing slow movement, a Largo, is the heart of the sonata, conceptually as well as rhythmically. Stern but harmonically ambiguous chords lead to a delicate, nostalgic aria supported by a gentle heartbeat figure in the bass. This is soon supplanted by a long, flowing, rhapsodic section of quiet rumination. The opening theme, now with a more murmuring accompaniment, returns in more ornamented garb to escort the movement to its conclusion. The final movement, Presto, non tanto, makes a short transition from the Largo with a few swelling introductory bars that lead to the urgent, driving first theme of what turns out to be a rondo; this B minor material alternates with a contrasting, chord-launched section in the major designed to showcase the performer's agile fingerwork. Elements of both sections overlap for a grand coda.