There are several differences in costs and coverage among Original Medicare, Private Fee-for-Service (PFFS) plans, and Health Maintenance Organizations (HMOs). The table below compares these three types of Medicare plans. If you are interested in joining a PFFS plan, make sure to speak to a plan representative for more information.
| Original Medicare | Medicare PFFS | Medicare HMO |
| See any provider and use any facility that accepts Medicare (participating or non-participating) | See any provider, but may pay more when seeing out-of-network providers | See only in-network providers |
| Visit doctors anywhere in the U.S. | Visit doctors anywhere in the U.S., but may pay more when seeing out-of-network providers | Visit doctors only in your plan’s service area, except in emergencies or when care is urgently needed |
| Do not need referrals for specialists | Do not need referrals for specialists | Typically need referrals for specialists |
| Does not cover vision, hearing, or dental services | May cover additional services, including vision, hearing, and dental (additional benefits may increase your premium or other out-of-pocket costs) | May cover additional services, including vision, hearing, and dental (additional benefits may increase your premium or other out-of-pocket costs) |
| Sign up for a stand-alone prescription drug plan (Part D) | Plan may provide prescription drug coverage (if it does not, you can join a stand-alone plan) | In most cases, plan provides prescription drug coverage (you may be required to pay higher premium) |
| Charged for standardized Part A and Part B costs (premiums and other cost-sharing for Part D vary depending on plan) | Cost-sharing varies depending on plan | Cost-sharing varies depending on plan |
| No out-of-pocket limit | Annual out-of-pocket limits for in-network and out-of-network care (maximum is $6,700 in 2018) | Annual out-of-pocket limit for in-network care (maximum is $6,700 in 2018) |
If you have Original Medicare, you also have the choice to purchase a supplemental insurance policy, or Medigap. Medigap plans cover Medicare cost-sharing and offer other benefits, but charge an additional premium. You cannot enroll in a Medigap plan if you have Medicare Advantage.