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. 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’s required by law in many situations. For Original Medicare, providers must give you an ABN before providing a service they believe Medicare will not cover. This gives you the chance to make an informed decision about your care and your finances.
• 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

This is the most important part. When you receive an ABN, you must choose one of three options:

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.
• If the appeal fails, you are responsible for paying.
• 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

Behind the scenes, the ABN option you chose determines how the claim is coded:

• GA modifier (Option 1 was signed): The provider bills Medicare with a GA modifier, indicating an ABN is on file. If Medicare denies the claim, you are financially responsible — but you can appeal.
• GZ modifier (no ABN was obtained): The provider bills Medicare, but because no ABN was signed, you are not financially responsible if the claim is denied. Medicare automatically assigns liability to the provider.

If you are ever billed for a denied service and you did not sign an ABN, this is the key fact to raise with the provider’s billing office.

Should You Appeal?

What To Do Next

1. Find your copy of the ABN. Check which option you selected. This determines your next steps. Your provider is required to give you a copy.
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 you never received an ABN and are being billed for a denied service, contact the provider’s billing office. Without a valid ABN, the provider generally cannot hold you financially responsible. The GZ modifier should have been applied, making the provider liable.
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 Interactive: Advance Beneficiary Notice (ABN)
• Center for Medicare Advocacy: The Medicare ABN — A Tool for Limiting Beneficiary Liability

Frequently Asked Questions