Can sonata form appear outside the first movement of a sonata or symphony?

Yes, sonata form can certainly appear in movements other than the first. While it is most strongly associated with the opening movement of Western instrumental genres like sonatas, symphonies, and string quartets, it is not restricted to that position.1

Composers frequently utilized sonata form in later movements to provide structural depth and thematic development. Its application in other movements includes:2

• Slow Movements: Sonata form is sometimes used for the second movement, though the development section is often omitted to maintain appropriate proportions.2
• Finales: It is a common pattern for the final movement, often appearing in a hybrid structure known as sonata-rondo, which combines elements of both forms.2
• Dance Movements: In some instances, such as in the symphonies of Ludwig van Beethoven and Franz Schubert, the binary structures of a scherzo and its trio were expanded into complete sonata-form structures.2

As the Classical period progressed, the principles of thematic development and key contrast inherent in sonata form increasingly influenced the design of entire multimovement works.2