Health Maintenance Organization (HMO) plans typically have a lower premium cost with copays for services. However, HMO's lack the freedom found in other plans. They require the member to see in-network providers and to go through an in-network primary care physician before seeing a specialist.
Preferred Provider Organization (PPO) plans don't require the member to see primary care physician before seeing a specialist. Plus, unlike the HMO, members can also see a provider who is out of the insurer’s network but pay more to do so. PPO plans vary in deductible and copayment options.
Health Savings Accounts (HSA) are coupled with high deductible PPO health plans. Pre-tax earnings deposited in the HSA can accumulate and grow year after year if not used. To preserve the tax benefits of these accounts, the money in an HSA can only be used to pay for qualified medical expenses (as defined by the IRS).