Diabetes affects approximately one in 10 persons in the United States † and is a risk factor for severe COVID-19 (1), especially when a patient's diabetes is not well managed (2). The extent to which the COVID-19 pandemic has affected diabetes care and management, and whether this varies across age groups, is currently unknown. To evaluate access to and use of health care, as well as experiences, attitudes, and behaviors about COVID-19 prevention and vaccination, a nonprobability, Internet-based survey was administered to 5,261 U.S. adults aged ≥18 years during February-March 2021. Among respondents, 760 (14%) adults who reported having diabetes currently managed with medication were included in the analysis. Younger adults (aged 18-29 years) with diabetes were more likely to report having missed medical care during the past 3 months (87%; 79) than were those aged 30-59 years (63%; 372) or ≥60 years (26%; 309) (p<0.001). Overall, 44% of younger adults reported difficulty accessing diabetes medications. Younger adults with diabetes also reported lower intention to receive COVID-19 vaccination (66%) compared with adults aged ≥60 years § (85%; p = 0.001). During the COVID-19 pandemic, efforts to enhance access to diabetes care for adults with diabetes and deliver public health messages emphasizing the importance of diabetes management and COVID-19 prevention, including vaccination, are warranted, especially in younger adults., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Matthew D. Weaver reports institutional support to Monash University from WHOOP, Inc., institutional grant support from the National Heart, Lung, and Blood Institute, National Institutes of Health (NIH), the National Institute of Occupational Safety and Health (NIOSH), and consulting fees from the National Sleep Foundation and the University of Pittsburgh, outside the current work. Shantha M.W. Rajaratnam reports institutional grant support to Monash University from WHOOP, Inc. and the Cooperative Research Centre for Alertness, Safety, and Productivity; and institutional consultancy fees from Teva Pharma, Australia, Circadian Therapeutics, Vanda Pharmaceuticals, BHP Billiton, and Herbert Smith Freehills; and honoraria from Cooperative Research Centre for Alertness, Safety, and Productivity. Mark E. Howard reports an institutional grant to Monash University from WHOOP, Inc. Mark É. Czeisler reports institutional grants paid to Monash University from WHOOP, Inc. and the CDC Foundation, with funding provided by BNY Mellon, and support from the Australian-American Fulbright Foundation, with funding provided by The Kinghorn Foundation, and consulting fees from Vanda Pharmaceuticals (September 2019–January 2020). Charles A. Czeisler reports institutional support from WHOOP, Inc., and serves as the incumbent of an endowed professorship provided to Harvard Medical School by Cephalon, Inc. in 2004; grant support from Delta Airlines, Jazz Pharmaceuticals PLC, Inc., Philips Respironics, Inc., Puget Sound Pilots, Regeneron Pharmaceuticals and Sanofi SA, ResMed, Teva Pharmaceuticals Industries, Ltd, and Vanda Pharmaceuticals; royalty payments from Philips Respironics, Inc. for the Actiwatch-2 and Actiwatch-spectrum devices; personal consultancy fees from Physician’s Seal, State of Washington Board of Pilotage Commissioners, With Deep, and Vanda Pharmaceuticals; lecture fees from Teva Pharma Australia and Tencent Holdings, Ltd, and payment as Chair for the Sleep Timing and Variability Consensus Panel, National Sleep Foundation; payment for expert testimony from Aegis Chemical Solutions, Amtrak, Casper Sleep, Inc., C&J Energy Services, Enterprise Rent-A-Car, Dallas Police Association, FedEx, PAR Electrical Contractors, Inc., Puget Sound Pilots, Schlumberger Technology Corp., Union Pacific Railroad, United Parcel Service and Vanda Pharmaceuticals; travel support from Tencent Holdings, Ltd., Aspen Brain Institute, Bloomage International Investment Group, Inc., Stanley Ho Medical Development Foundation, German National Academy of Sciences, the National Safety Council, and the National Sleep Foundation; member of the following advisory boards: AARP, Institute of Digital Media and Child Development, Klarman Family Foundation, and U.K. Biotechnology and Biological Sciences Research Council; equity interest in Vanda Pharmaceuticals; and institutional educational gifts from Johnson & Johnson, Harmony Biosciences, LLC, and Philips Respironics, Inc., ResMed, and Vanda Pharmaceuticals to Brigham and Women’s Hospital. No other potential conflicts of interest were disclosed.