Assignment determines who receives Medicare payment, how much a provider may collect, and what the beneficiary may owe. Participation and assignment are related, but they are not the same:

• Participating providers accept assignment on all Medicare-covered services subject to their participation agreement.
• Non-participating providers may generally decide whether to accept assignment on eligible claims.
• Certain providers and services require assignment regardless of participation status.

Accepting Assignment

When you accept assignment, you agree to accept the Medicare-approved amount as payment in full for the covered service. Medicare pays its portion directly to you. The beneficiary is responsible only for applicable:

• Deductible
• Coinsurance
• Copayment
• Permitted charges for noncovered services

You must write off the difference between your billed charge and the Medicare-approved amount. You may not bill that difference to the beneficiary.

Assigned-Claim Example

Assume the Medicare-approved amount is $100:

• Medicare payment: $80
• Beneficiary coinsurance: $20
• Total provider payment: $100

If assignment is accepted, you may not bill the beneficiary an additional amount because your regular charge is higher than $100.

This example assumes an 80% Medicare payment and 20% coinsurance. It does not account for deductibles, secondary insurance, payment adjustments, or services with different cost-sharing requirements.

Not Accepting Assignment

A nonassigned claim is an eligible claim submitted by a non-participating provider who does not accept assignment. When assignment is not accepted:

• Medicare generally pays the beneficiary.
• The beneficiary is responsible for paying the provider.
• The provider may charge more than the Medicare-approved amount when permitted.
• The total charge may not exceed the applicable limiting charge.
• Mandatory-assignment requirements continue to apply.

Participating providers cannot choose nonassignment on individual Medicare-covered claims subject to their participation agreement.

Assigned and Nonassigned Claims Compared

Assigned Claim

• Medicare pays the provider directly.
• The provider accepts the Medicare-approved amount as payment in full.
• The beneficiary is responsible for applicable deductible, coinsurance, or copayment.
• The provider may not bill above the Medicare-approved amount.
• The limiting charge does not apply.

Nonassigned Claim

• Available only to an eligible non-participating provider.
• Medicare generally pays the beneficiary.
• The beneficiary is responsible for paying the provider.
• The provider may charge above the Medicare-approved amount when permitted.
• The provider may not charge more than the applicable limiting charge.

Limiting Charge

For eligible nonassigned claims, the limiting charge is generally 115% of the non-participating fee schedule amount. For example, assume:

• Participating fee schedule amount: $100
• Non-participating fee schedule amount: $95
• Limiting charge: $95 × 115%
• Maximum charge: $109.25

The maximum charge in this simplified example is $109.25, not $115. Actual payment and beneficiary liability depend on the applicable fee schedule, locality, facility setting, service, deductible, coinsurance, and other Medicare payment requirements.

Mandatory Assignment

Certain practitioners must accept assignment for their Medicare-covered practitioner services. These include:

• Anesthesiologist assistants
• Certified nurse-midwives
• Certified registered nurse anesthetists
• Nurse practitioners
• Clinical psychologists
• Clinical social workers
• Clinical nurse specialists
• Registered dietitians and nutrition professionals
• Physician assistants
• Marriage and family therapists
• Mental health counselors
• Mass immunization roster billers

Assignment may also be mandatory for particular services or beneficiary circumstances. Do not assume that non-participating status permits nonassignment for every claim.

Medigap Crossover

When assignment is accepted and the claim meets applicable crossover requirements, Medicare may forward the processed claim information to the beneficiary’s Medigap insurer.
This can reduce the need to submit a separate supplemental claim. The Medigap insurer may then pay eligible deductible and coinsurance amounts directly to the provider or supplier.

Before Billing a Beneficiary

Before collecting payment:

• Confirm your Medicare participation status.
• Determine whether assignment is mandatory.
• Decide whether to accept assignment when a choice is available.
• Review the applicable Medicare-approved amount and limiting charge.
• Explain the beneficiary’s expected financial responsibility.
• Submit the correct assignment indicator on the claim.
• Review the remittance advice and issue any required adjustment or refund.