Background . Nursing home (NH) residents have been disproportionately affected by the coronavirus disease 2019 (COVID-19) pandemic and are prioritized for vaccination . NH residents are generally at increased risk of poor outcomes due to advanced age, frailty, and complex health conditions . We report monthly incidence rates of deaths, hospitalizations, and emergency department (ED) visits during ten pre-pandemic years (2010-2019) and 2020 to provide context for assessments of COVID-19 vaccine safety in NH residents . Methods . We observed deaths, hospitalizations, and ED visits among all Ontarians living in NHs using health administrative databases . Monthly incidence rates were calculated by month, by sex, and by age group . Direct comparisons between months were assessed using one-sample t-tests; direct comparisons by age and sex were assessed using chi-squared tests . Results . From January 1 , 2010 through December 31 , 2019, there were, on average , 83,453 (SD : 652.4) Ontarians living in NHs in any given month, with an average of 2.3 (SD : 0.28) deaths , 3.1 (SD : 0.16) hospitalizations, and 3.6 (SD : 0.17) ED visits per 100 residents per month . Mortality rates were higher for men (p <0.001) and residents aged [≥] 80 years (p <0.001). Hospitalization and ED visit rates were higher for men but were lower for residents aged [≥] 80 years . From January to October 2020, the number of NH residents declined markedly . Mortality rates were increased in 2020 compared to 2010-2019, but hospitalization and ED visit rates were reduced in 2020 compared to 2010-2019 (p <0.001). Conclusion . We identified relatively consistent monthly mortality, hospitalization, and ED visit rates during ten pre-pandemic years . Marked differences in these rates were observed during 2020, coinciding with heightened COID-19 infection rates and restrictions . These results provide context to the assessment of COVID-19 vaccine safety outcomes in this high-risk population.