Medicare says a provider that accepts assignment agrees to accept the Medicare-approved amount as payment in full for covered services and to charge the patient only the applicable deductible and coinsurance. Most providers accept assignment, but patients can verify before care.
Some non-participating providers may not accept assignment for a claim and, in many cases, can charge up to the Medicare limiting charge for applicable physician services. Other provider types and services can have different rules.
- Original Medicare or Medicare Advantage?
- Does each provider/supplier accept assignment?
- Medicare-approved amount
- Part B deductible status
- Applicable coinsurance
- Any supplemental coverage
- QMB status
- Whether any non-assignment charge is actually permitted for this service
Ask the assignment question before using a cost estimate
If a provider accepts assignment, the Medicare-approved amount—not the provider’s sticker price—is the key base for normal Part B patient cost sharing.
For an infusion, also ask how the facility and any separately billing clinicians participate. Hospital outpatient departments and physician offices can generate different service lines.
Do not overgeneralize the 15% limiting charge
Medicare describes a limiting charge for many services from non-participating providers, but the rule is not a universal extra 15% on every Part B drug or facility bill.
Use Medicare’s provider-specific guidance and the actual claim setting before telling a patient an excess charge applies.
Supplemental coverage can change the final patient amount
Medigap, Medicaid, employer retiree coverage or other insurance may pay some Medicare cost sharing. Assignment status is one cost variable; it does not replace coordination-of-benefits analysis.
If the patient has QMB, the QMB balance-billing protection is more important than an ordinary assignment estimate because the patient cannot be billed Medicare cost sharing for covered services.
Use the source that actually controls your case
MedicineCostHelp can organize the problem, but the member-specific plan, Medicare program, provider billing record or assistance program makes the actual decision. Save written determinations and reference numbers so the next person does not have to reconstruct the case from scratch.