Background/Objectives: We still do not clearly know whether COVID-19 continues to impose a greater clinical burden than influenza in the “post-pandemic” era. Our study quantified and compared monthly COVID-19 and influenza hospitalization incidence among adult subgroups from October 2022 through December 2024. We assessed vaccine coverage trends and examined vaccination status among those hospitalized. Methods: Using the Veradigm linked claims and electronic health record dataset, we conducted a non-interventional, retrospective cohort study; three monthly cohorts included individuals aged 65+, high-risk (HR) adults (defined as adults 18+ with HR conditions and/or aged 65+), and adults aged 50-64 years who were enrolled with both medical and pharmacy coverage. We estimated monthly cumulative incidence of COVID-19 and influenza-related hospitalizations, vaccination coverage rates, and the proportion of hospitalized individuals who had received seasonal vaccines. Results: COVID-19 hospitalizations consistently exceeded those of influenza across months and populations. Among adults aged 65+, COVID-19 hospitalization rates were 2–3 times higher than influenza in winter and 20–30 times higher during off-season months, with similar trends observed in high risk adults. COVID-19 incidence surged in summer, while influenza remained seasonally confined. Vaccination coverage for influenza peaked near 50% annually; COVID-19 coverage was lower, peaking at ~26% by December each year. Most hospitalizations occurred among unvaccinated individuals, particularly for COVID-19. Conclusions: COVID-19 continues to impose a substantial, year-round burden, particularly in older and high-risk adults, exceeding that of influenza. The high proportion of unvaccinated hospitalizations highlight a critical gap in prevention efforts and underscore the need for improved public health messaging and vaccine adoption.