Original Medicare denied a service after you signed an ABN that may not be valid? What the rule says and how to appeal.
Checked against the current rules on September 25, 2026.
A denial for a service after you signed an ABN that may not be valid isn't the end of the story — Original Medicare has to follow specific coverage rules, and a denial that doesn't square with those rules is exactly the kind of appeal that tends to win.
Here's what the rule actually requires, what evidence usually turns a denial around, and the deadline you're working against.
What the rule requires
Coverage for a service after you signed an ABN that may not be valid under Original Medicare is governed byAdvance Beneficiary Notice of Non-coverage (ABN) and§ 411.408 Refunds of amounts collected for physician services not reasonable and necessary, payment not accepted on an assignment-related basis.. Original Medicare generally cannot apply a stricter test than what these rules require.
Questions that decide it
Before you appeal, these are the facts that usually decide whether a denial like this holds up:
Was an option already checked on the form before you looked at it, instead of you choosing it yourself?
Did the form include a genuine cost estimate for the service, not left blank or wildly understated?
Were you asked to sign it during an emergency or urgent-care situation?
Did anyone review the notice with you and answer questions before you signed, or was it just handed over to sign?
What a winning appeal has to show
An appeal that wins usually includes:
A copy of the signed ABN itself — A pre-selected option, a missing or unreasonable cost estimate, no signature/date, or issuance during an emergency can each make an ABN defective — and a notifier who gave defective notice can't rely on it to bill you, and must refund anything already collected. (You or your family provide this.)
The ABN's own signed date compared against the actual dates of service being billed — For an ongoing course of treatment, a single ABN generally only protects the provider for about a year — a real Medicare Appeals Council decision held a provider liable, not the beneficiary, when the notice on file was more than two years old. (You or your family provide this.)HHS Departmental Appeals Board, Medicare Appeals Council — In the Case of Rx Home Care, Inc. (November 3, 2009)
Your deadline to appeal
120 days from the date on the Medicare Summary Notice — 120 calendar days from when you receive it (42 CFR § 405.942(a)), with receipt presumed to be 5 days after the notice's own date unless shown otherwise.42 CFR 405.942
Your Medicare contractor itself then has its own clock to decide. 60 calendar days from when the MAC receives your timely request. Each time you submit new evidence after filing, that 60-day clock is extended by up to 14 more calendar days for that submission (42 CFR § 405.950(a), (b)(3)) — this can happen more than once.
Questions people ask
- Can your Medicare contractor just say it's "not medically necessary" with no further explanation?
- The denial notice has to explain the basis for the decision and tell you how to appeal. If it doesn't point to a specific rule or criteria, that's itself worth raising in your appeal — you're entitled to know what standard was applied.
- What if I don't have all the evidence listed above?
- Include what you have. An appeal with partial evidence and a clear explanation of the rule still gets a real review — it doesn't need to be complete to be worth filing.
Sources — last checked September 25, 2026
- § 411.408 Refunds of amounts collected for physician services not reasonable and necessary, payment not accepted on an assignment-related basis.as of September 24, 2026
- 42 CFR 405.942as of September 23, 2026
- Advance Beneficiary Notice of Non-coverage (ABN)as of September 25, 2026
- HHS Departmental Appeals Board, Medicare Appeals Council — In the Case of Rx Home Care, Inc. (November 3, 2009)
Related
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By CaseWhy Appeals editorial. See how this content is produced. Not legal advice. Not affiliated with or endorsed by Medicare, CMS, or any health plan. A product of CaseWhy LLC.
