The COVID-19 pandemic has led to substantial increases in the use of telehealth and virtual care in the US. Differential patient and provider access to technology and resources has raised concerns that existing health disparities may be extenuated by shifts to virtual care. We used data from one of the largest providers of employer-sponsored insurance, the California Public Employees' Retirement System, to examine potential disparities in the use of telehealth. We found that lower-income, non-White, and non-English-speaking people were more likely to use telehealth during the period we studied. These differences were driven by enrollment in a clinically and financially integrated care delivery system, Kaiser Permanente. Kaiser's use of telehealth was higher before and during the pandemic than that of other delivery models. Access to integrated care may be more important to the adoption of health technology than patient-level differences.