Opera and oratorio overtures exist in an indeterminate state between purely symphonic and dramatic music. While they can be and often are extracted for symphonic programs, they are ultimately tied to the story to which they grant the audience a preview of the story and music yet to come. Those that are easily extracted are so independent due to their structure, one well known to the symphony: the sonata form. In studying overtures from the 19th century, however, one can trace a decline of the sonata form overture for one that is more subservient to the dramatic story soon to follow it. In this paper, three representatives of the early, mid and late period of the highlight this steady shift away from sonata form. Using Hepokoski and Darcy’s Elements of Sonata Theory: Norms, Types, and Deformations in the Late-Eighteenth-Century Sonata, I will categorize these overtures into one of the five sonata types listed therein. The increasing number of deformations as one moves through the overtures chronologically will illustrate the deliberate decline of use of the sonata form for the overture in favor of a clearer reflection of the upcoming story.