We estimate the role of firms in worker health care utilization. Using linked administrative data on Austrian workers from 1998–2018, we exploit mobility between firms to estimate how much a firm contributes to worker-level differences in utilization in a setting with non-employer provided universal health care. We find that firms are responsible for nearly 30 percent of the variation in across-worker health care expenditures. Effects are not driven by changes in geography or industry. We then estimate a measure of relative firm-specific utilization and explore existing correlates to help explain these effects.