Medicare denied a claim. What now?

A denial letter is written to sound final. It isn’t. It’s the opening position in a process that is heavily tilted toward people who respond — and most people never do, even though appealed denials are frequently overturned.

First, figure out which kind of denial you have

Original Medicare sends a Medicare Summary Notice (MSN) every three months. If a claim was denied, it appears there with a code and a short reason. You generally have 120 days from the date on the notice to ask for a “redetermination” — the first level of appeal.

Medicare Advantage (a plan run by a private insurer) sends its own denial notice, and the clock is faster: usually 60 days to ask the plan for reconsideration. If the plan still says no, the case is automatically sent to an independent reviewer — you don’t have to request that step.

The deadline is printed on the notice itself. Find it, write it on the outside of the envelope, and put it on the calendar today. Everything else can happen this week; the deadline cannot slip.

Call the billing office before you write anything

A surprising number of denials are clerical: a wrong procedure code, a missing diagnosis code, a claim sent to the wrong payer. Call the provider’s billing office, read them the denial reason, and ask one question: “Can this be corrected and resubmitted?” If yes, they fix and resubmit it, and no appeal is needed. This one call resolves many denials in under a week.

If you do need to appeal

For Original Medicare, follow the instructions on the MSN: circle the denied claim, sign it, and mail it in — or use the redetermination request form. Attach anything that supports the claim, especially a short letter from the doctor explaining why the service was medically necessary. That letter is the single most persuasive document in the file.

Keep it factual and short. You’re not writing an essay; you’re giving a reviewer a reason to say yes.

Write everything down

Every call: the date, the name of the person, and what they said. Every document: keep a copy. If the appeal escalates, this log is the difference between “we have no record of that” and a case you can win. A single folder — paper or photos — is enough.

You don’t have to do this alone

Every state has a SHIP — a State Health Insurance Assistance Program — with counselors who help with Medicare appeals for free. They are not selling anything. Find yours at shiphelp.org or by calling 1-877-839-2675. For a denial involving a lot of money, call them before you file.

This is organizational help, not medical or legal advice. The notice in your hand is authoritative about deadlines and process — when it disagrees with anything here, follow the notice.