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.

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," or the amount above the Medicare-approved amount that non-participating providers can charge). This means you are responsible for up to 35% (20% coinsurance + 15% limiting charge) of Medicare’s approved amount for covered services.
• Minnesota care limiting charge does not permit any fees beyond the Medicare limiting charge. This applies to Medicare beneficiaries seeing Minnesota providers. 
• 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.