Medicare ABN (Advance Beneficiary Notice) Guide

What This Means

Your healthcare provider gave you a form called an Advance Beneficiary Notice of Noncoverage (ABN) before providing a service, test, or supply under Original Medicare. This form is your provider’s way of telling you: “We don’t think Medicare will pay for this, and here’s what it will cost.”

The ABN is not a denial. It is a heads-up that a denial is likely, and it gives you the choice of how to proceed. What you choose on the ABN has a direct effect on whether you can appeal later and who pays if Medicare says no.

Why This Happens

• Your provider expects Medicare won’t cover the service. This could be because the service doesn’t meet Medicare’s medical necessity rules, it exceeds a frequency limit, or it falls outside Medicare’s coverage criteria for your diagnosis.
• It is required to transfer liability in specified situations. An expected medical-necessity denial generally requires an ABN; experimental laboratory tests can also require one. Services excluded by law or outside a Medicare benefit category can have optional notices instead. The reason for noncoverage matters (CMS notice rules).
• It applies to Original Medicare only. ABNs are used with Original Medicare (Parts A and B). Medicare Advantage plans have their own notice requirements.

The Three ABN Options — What Each One Means

When an ABN is required to transfer potential liability, review the listed service, reason and estimated cost, then choose an option yourself. A provider cannot choose for you. A voluntary notice for a service excluded from coverage does not require an option selection or signature. People with Medicaid or Qualified Medicare Beneficiary coverage have additional billing protections; ask the provider or SHIP how those apply (CMS ABN instructions).

Option 1: “I want the service. Bill Medicare.”

• Your provider performs the service and submits a claim to Medicare.
• If Medicare denies the claim, you can appeal the denial.
• A valid ABN may make you responsible if Medicare does not pay. Check the decision and any other coverage or billing protections.
• This is usually the best choice if you think Medicare should cover the service or if you want to preserve your right to appeal.

Option 2: “I want the service. Don’t bill Medicare.”

• Your provider performs the service but does not submit a claim to Medicare.
• You pay the full cost out of pocket.
• Because no claim is filed, you cannot appeal. There is no Medicare decision to challenge.
• Choose this only if you’re certain Medicare won’t cover it and you’re willing to pay the full amount.

Option 3: “I don’t want the service.”

• The service is not performed.
• You owe nothing.
• There is no claim and no appeal.

What the Billing Modifiers Mean

Billing modifiers help Medicare process the claim, but a modifier or signature alone does not prove the notice was valid:

• GA modifier: The provider reports that a required waiver-of-liability notice was issued. Ask for the actual ABN if you dispute responsibility; you can appeal the Medicare decision.
• GZ modifier: The provider expects a denial because the service was not reasonable and necessary and did not issue an ABN. This generally leaves the provider responsible for that denial. It is not the correct modifier for every service furnished without an ABN.

Ask the billing office to explain the denial reason and the liability shown on your MSN. Do not assume a statutory exclusion and a medical-necessity denial have the same notice rules.

Should You Appeal?

What To Do Next

1. Find your copy of the ABN. Your provider must give you a copy. Check the service, stated reason, estimated cost, date and option selected. A generic agreement to pay anything Medicare denies is not a substitute for a valid ABN.
2. If you chose Option 1 and the claim was denied, you have the right to appeal. Follow the instructions on your Medicare Summary Notice (MSN). Ask your doctor for supporting documentation.
3. If you chose Option 2, you are responsible for payment. However, if you believe you were pressured into choosing Option 2 or didn’t understand what you were signing, contact your State Health Insurance Assistance Program (SHIP) for guidance.
4. If a required ABN was missing or invalid, ask the billing office to review the liability and compare the charge with your MSN. Do not assume every denial required an ABN or that a particular modifier applies solely because you did not sign one.
5. If you haven’t had the service yet and just received an ABN, take time to read it carefully before signing. Ask your provider to explain why they think Medicare won’t cover it. You can choose Option 1 to preserve your appeal rights.
6. Get free help. Contact your State Health Insurance Assistance Program (SHIP) or call 1-800-MEDICARE (1-800-633-4227) for help understanding your ABN or filing an appeal.

Sources

• CMS: Fee-for-Service Advance Beneficiary Notice (ABN)
• CMS: ABN Form Instructions
• Medicare.gov: Your Medicare Rights & Protections (Advance Beneficiary Notice)
• CMS: ABN tutorial — required notice details, patient choices and Medicaid/QMB guidance.
• CMS: Claims Processing Manual, chapter 30 — scope, required versus optional use, and notice validity.
• CMS MLN006266: Medicare Advance Written Notices of Non-coverage

Frequently Asked Questions