This corpus-based study focuses on the nine English central modal verbs (can, could, will, would, may, might, shall, should, and must) across the two chosen genres of the COCA corpus – Spoken and Academic genres, which show the greatest number of differences in terms of genre characteristics, such as formality or intended audience. Because research on modal verbs across genres, especially one inclusive of the spoken genre, is limited, this study investigates these two genres to test the hypothesis that the general genre characteristics influence the choice of modal verbs. As a result, the distribution of modal verbs across the different genres differs too. The results suggest that genre can indeed be indicative of the frequency and use of modal verbs, which may be ascribed to two language processes colloquialization and democratization.