If you have Original Medicare, your Part B costs once you have met your deductible can vary depending on the type of provider you see. For cost purposes, there are three types of provider, meaning three different relationships a provider can have with Medicare. A provider’s type determines how much you will pay for Part B-covered services.

1. Participating providers accept Medicare and always take assignment. Taking assignment means that the provider accepts Medicare’s approved amount for health care services as full payment.
   • These providers are required to submit a bill (file a claim) to Medicare for care you receive. Medicare will process the bill and pay your provider directly for your care. If your provider does not file a claim for your care, there are troubleshooting steps to help resolve the problem.
   • If you see a participating provider, you are responsible for paying a 20% coinsurance for Medicare-covered services.
   • Certain providers, such as clinical social workers and physician assistants, must always take assignment if they accept Medicare.
2. Non-participating providers accept Medicare but do not agree to take assignment in all cases (they may on a case-by-case basis). This means that while non-participating providers have signed up to accept Medicare insurance, they do not accept Medicare’s approved amount for health care services as full payment.
   • Non-participating providers can charge up to 15% more than Medicare’s approved amount for the cost of services you receive (known as the limiting charge). This means you are responsible for up to 35% (20% coinsurance + 15% limiting charge) of Medicare’s approved amount for covered services.
   • Some states may restrict the limiting charge when you see non-participating providers. For example, New York State’s limiting charge is set at 5%, instead of 15%, for most services. For more information, contact your State Health Insurance Assistance Program (SHIP).
   • If you pay the full cost of your care up front, your provider should still submit a bill to Medicare. Afterward, you should receive from Medicare a Medicare Summary Notice (MSN) and reimbursement for 80% of the Medicare-approved amount.
   • The limiting charge rules do not apply to durable medical equipment (DME) suppliers. Be sure to learn about the different rules that apply when receiving services from a DME supplier.
3. Opt-out providers do not accept Medicare at all and have signed an agreement to be excluded from the Medicare program. This means they can charge whatever they want for services but must follow certain rules to do so.
   • Medicare will not pay for care you receive from an opt-out provider (except in emergencies). You are responsible for the entire cost of your care.
   • The provider must give you a private contract describing their charges and confirming that you understand you are responsible for the full cost of your care and that Medicare will not reimburse you.
   • Opt-out providers do not bill Medicare for services you receive.
   • Many psychiatrists opt out of Medicare.

Providers who take assignment should submit a bill to a Medicare Administrative Contractor (MAC) within one calendar year of the date you received care. If your provider misses the filing deadline, they cannot bill Medicare for the care they provided to you. However, they can still charge you a 20% coinsurance and any applicable deductible amount.

Be sure to ask your provider if they are participating, non-participating, or opt-out. You can also check by using Medicare’s Physician Compare tool.