Allegro moderato, E major, 4/4 time

Adopting sonata form, the exposition is clearly discernible compared to the opening movements of the previous two piano sonatas. The first theme is presented in E major at the beginning, concluding with a half cadence in measure 20. Using this dominant chord as the tonic of a new key, the second theme is presented, and a further theme is introduced in B major (measure 33).

In later years, Schubert would construct the exposition with theme groups in three key areas by inserting a mediant key area between the tonic and dominant areas of the exposition (for details, refer to the commentary on Piano Sonata No. 21, D 960). From this perspective, this sonata can be positioned within the process of stylistic development, given that three themes are presented.

Unlike the previous two works, modulation is largely suppressed in the exposition of this sonata and actively employed in the development section. The development section (measures 54–79) is rich in fluctuations not only in terms of modulation but also dynamics.

In measure 80, the opening theme returns in A major, marking the recapitulation. Recapitulation in the subdominant key is famously seen in the Mozart's Piano Sonata in C major, K. 545first movement, but it was also a technique Schubert himself had already used in Piano Sonata No. 2, D 279. Just as the exposition progressed to the key a fifth above, the second and third themes return in the tonic key, a fifth above A major, bringing the movement to a close.