PurposeTo evaluate the association between health system affiliation and hospitals’ reported responses to the COVID-19 pandemic. MethodsBetween September 14, 2020 and November 20, 2020, we conducted a survey of hospital administrators. We linked these survey results to county-level data on COVID-19 incidence and hospital affiliation data from the Agency for Healthcare Research and Quality Compendium on US Health Systems. We analyzed the association between health system affiliation and hospitals’ reported responses to the COVID-19 pandemic. ResultsWe analyzed data from 217 general, short-stay, acute-care hospitals who responded to the survey. Health system affiliated hospitals reported increased adoption of policies to accept fewer patients in transfer (adjusted OR 2.06, 95% CI 1.01 – 4.21, p = 0.047), increased adoption of new ICU telemedicine programs (adjusted OR 4.90, 95% CI 1.09 – 22.1, p = 0.039), and decreased repurposing of medical-surgical units as ICUs (adjusted OR 0.51, 95% CI 0.27 – 0.97, p = 0.041). ConclusionsHospitals affiliated with health systems responded differently to the pandemic than non-system affiliated hospitals, including in ways that may have promoted efficient management of critical care demand and supply across hospitals. These findings suggest interhospital coordination may play an important role in disaster and pandemic preparedness.