Medicare (Original) denied your claim — here's how to appeal
Federal coverage with its own five-level appeal ladder, starting from the Medicare Summary Notice rather than an EOB.
Plans this covers
Deadlines and how the process runs
- Original Medicare denials appear on the quarterly Medicare Summary Notice (MSN), not on a commercial EOB.
- The first level is a redetermination filed with the Medicare Administrative Contractor, generally within 120 days of the MSN.
- Advance Beneficiary Notices matter: if you were never given one before a non-covered service, you may not be responsible for the charge at all.
Rights that apply to every plan
- You generally have at least 180 days from the date on your denial notice (EOB) to file an internal appeal with your insurer.
- The insurer must decide standard internal appeals within 30 days for pre-service claims and 60 days for care you already received.
- Urgent cases get an expedited review — typically within 72 hours.
- If the internal appeal fails, you can request an independent external review, usually within 4 months of the final internal denial. The external reviewer's decision is binding on the plan.
- Self-funded employer plans follow ERISA rules; fully insured plans also fall under your state insurance department, which can be a second place to complain.
Denial codes you'll most likely see from Medicare (Original)
A real example
- The situation
- A routine screening billed as diagnostic and denied for frequency limits.
- What went wrong
- The provider coded the visit with a diagnostic code, which triggered a frequency edit that a screening code would not have.
- What worked
- The provider recoded the claim to the correct screening code and Medicare paid it at 100% with no patient share.
Appealing a Medicare (Original) denial, step by step
- 1Get the itemized bill from the provider and the EOB from the insurer, and line them up against each other.
- 2Find the denial code on the EOB and read what it actually means — it tells you whether the fix belongs to the insurer or the billing office.
- 3Note the appeal deadline printed on the denial notice and calendar it the same day.
- 4Request the clinical records or authorization number that answer the stated reason for denial.
- 5Send a written internal appeal that names the claim number, quotes the denial code, and states the specific correction you want.
- 6If it is upheld, request an independent external review before that window closes.
Medicare (Original) appeal FAQs
How do I appeal an Original Medicare denial?
Start with a redetermination request to the Medicare Administrative Contractor listed on your Medicare Summary Notice, generally within 120 days of the notice date. There are five levels in total, ending at federal district court.
What is an Advance Beneficiary Notice and why does it matter?
It is a form providers must give you before delivering a service Medicare is likely to deny, so you can decide whether to accept the cost. If you never signed one and the service was denied as non-covered, you generally cannot be billed for it.
Does Medicare have a deadline to respond to my appeal?
Yes — a redetermination is normally decided within 60 days of receipt.
Let BillCheck write the Medicare (Original) appeal for you
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BillCheck provides informational analysis only and is not legal, medical, or financial advice. Verify all details before submitting any correspondence to insurers or providers. Deadlines and processes vary by plan — the notice you received governs.