Much research has focused on differences in hospital prices paid by private (commercial) versus public (Medicare and Medicaid) health insurers. Far less is known about price differences across commercial payers-health maintenance organizations (HMOs) or preferred provider organizations (PPOs) versus other payers, such as casualty (automobile), workers' compensation, and travel insurers. We found that other insurers had far less negotiating power with hospitals than commercial HMO/PPO insurers did. In the period 2010-16, the median price paid by HMO/PPO insurers for hospital services in Florida increased from 1.9 times to 2.5 times the Medicare price, respectively, while the median price paid by other insurers increased from 2.8 times to 3.8 times the Medicare price. Commercial HMO/PPO insurers' prices were similar across major hospital systems, regardless of ownership, while other insurers' prices differed substantially across systems. In 2016 the twenty hospitals with the highest prices (7.8-14.1 times the Medicare rate) for other insurers in Florida were all affiliated with the Hospital Corporation of America. These hospitals generated 24 percent of their commercial net revenue (median) from other payers, despite treating a relatively small proportion of patients covered by these payers. Protecting patients with other insurance from high hospital prices requires efforts by policy makers, hospitals, and insurers.