Background: Respiratory syncytial virus (RSV) is the leading cause of hospitalizations and lower respiratory tract diseases in infants. Objectives: The objective is to examine RSV- and bronchiolitis-associated hospitalizations and emergency department (ED) visits among infants < 1 year of age in the United States (US). Methods: In this retrospective cohort study, RSV and bronchiolitis were identified in the 2019-2023 HCUP National (Nationwide) Inpatient Sample (NIS) and Nationwide Emergency Department Sample (NEDS). These datasets are the largest all-payer databases in the US. Sample-weighted numbers, overall hospitalization and ED visit rates per 1000 and 95% CIs, and those stratified by race and ethnicity (available for 2019-2022) or insurance status were reported. The weighted number of newborn birth hospitalizations was used as the denominator. Results: In 2019-2023, 276,655 RSV and 413,645 bronchiolitis hospitalizations and 895,645 RSV and 1,543,076 bronchiolitis ED visits were observed. Race and ethnicity data showed that American Indian and Alaska Native (AIAN) infants had the highest hospitalization rates in 2019-2022 (RSV: 28.5 [95% CI: 24.1-32.9] per 1000; Bronchiolitis: 42.6 [95% CI: 35.6-49.6] per 1000). In the ED, the visit rates were comparable for AIAN, Hispanic, White, and Black infants, and much lower for Asian Pacific Islander (API) infants. Infants covered by Medicaid/Children’s Health Insurance Program (CHIP) had the highest RSV and bronchiolitis hospitalization rates (20.5 [95% CI: 19.4-21.6] and 32.0 [95% CI: 30.2-33.9] per 1000, respectively) and ED visit rates (72.6 [95% CI: 67.6-77.7] and 129.9 [95% CI: 119.1-140.8] per 1000, respectively). Infants covered by private insurance had hospitalization rates of 12.5 (95% CI: 11.8-13.3) and 17.6 (95% CI: 16.5-18.7) per 1000 for RSV and bronchiolitis, respectively. In the ED, infants covered by private insurance had rates of 33.5 (95% CI: 30.5-36.5) and 53.4 (95% CI: 48.4-58.5) per 1000 for RSV and bronchiolitis, respectively. Conclusions: RSV remains an ongoing public health concern in the US. These nationally representative estimates demonstrate the importance of supporting RSV prevention products for all infants.