An EPO is a form of PPO, in which patients must visit a caregiver that is specified on its panel of providers (is a participating provider). If a visit to an outside (not participating) provider is made the EPO offers very limited or no coverage for the medical service. While similar to a PPO in that an EPO allows patients to go outside the network for care, if they do so in an EPO, in some circumstances they may be required to pay the entire cost of care. An EPO differs from an HMO in that EPO physicians may not receive capitation but instead may be reimbursed only for actual services provided. An EPO may also be defined as an organization identical to a preferred provider organization except that persons enrolled in the plan are eligible to receive benefits only when they use the services of the contracting providers. No benefits are available when non-contracting providers are used, except in certain emergency situations.