Free to read · nothing to sign · we're on your side

Everything you need to fight back —
in plain language.

A denial is built to make you give up. It won't. Here's how to get your letter, read what it actually says, understand the words they hide behind, and use the rights that are already yours.

01 · Get your denial letter

First, get the paper in your hands

You can't fight what you can't see. The single document that matters most is the written denial — sometimes called an Explanation of Benefits (EOB), an adverse benefit determination, or just the denial letter. It has to state a reason. That reason is the soft spot.

Log into your insurer's member portal(the website or app from the card in your wallet). Look for “Claims,” “Claims & EOBs,” or “Coverage.” Most denials are downloadable as a PDF the moment the claim processes.
Can't find it online? Call the member services number on the back of your card and say: “Please send me the written denial and the reason code for claim [number], in writing.” You are entitled to it.
Pull your records too.The denial is their side. Your provider's chart notes and your itemized bill are your side. You have a federal right (HIPAA Right of Access) to a copy of your own records — they must respond within 30 days, and they cannot charge more than about $6.50 for an electronic copy.

Keep a single folder — physical or a phone album — with the denial letter, your itemized bill, and anything your doctor wrote. That folder is your case.

02 · Read the denial

How to read a denial without panicking

These letters are written to sound final. They are not. Underneath the formatting there are only four things you need to find:

The reason.Somewhere it says why — “not medically necessary,” “out of network,” “no prior authorization,” a coding/billing problem. That phrase decides your whole strategy.

The claim details.Member ID, claim number, dates of service, the billed codes. You'll need these on every letter you send.

Your appeal rights.Buried near the end — usually “How to appeal” or “Your rights.” It names the deadline and where to send the appeal.

The deadline. A number of days from the date on the letter. Circle it. This is the only part with a clock on it.

If the letter genuinely makes no sense, that's not on you — these are written to confuse. A confusing denial is often a weak denial.

03 · The phrase they hide behind

What “medically necessary” really means

“Not medically necessary” is the most common denial — and one of the most beatable. It sounds like a medical fact. It isn't. It's a coverage opinion, usually made by a reviewer who never met you and never examined you, working from a file.

“Medically necessary” generally means care that was needed to diagnose, treat, or prevent a health condition — judged against accepted medical standards, not against whatever is cheapest for the plan. The person who actually treated you is the one with standing to say what you needed.

Your treating provider's written word — a note, a chart entry, an after-visit summary saying the care was needed — directly contradicts a paper reviewer. It is the single most persuasive thing an appeal can carry.
A documented link to a health condition matters. Care tied to a real diagnosis in the chart (an infection that could spread, gum disease connected to diabetes or heart disease, a procedure required before cancer or transplant treatment) has a far clearer necessity argument than care with no diagnosis written down.
You don't have to win the medical argument yourself.You have to get your provider's judgment in front of someone with the authority to overturn the decision. That's what an appeal does.

04 · Your rights & the clock

Your appeal rights and deadlines

You have the right to appeal a denial. That right is not a favor the insurer grants — it's built into how the system works. The mechanics are simple once someone lays them out.

Internal appeal first.You ask the insurer to reconsider. You can submit new information — your provider's note, records, a clear statement of why the denial is wrong.
External review next. If they uphold the denial, you can usually take it to an independent reviewer who does not work for the insurer. Their decision is binding on the plan.
Deadlines are real but generous. Internal-appeal windows are often around 180 days from the denial for many plans — but the exact number is on your letter and the clock starts at the date printed on it. File before it, even a short letter, to protect your rights. You can add detail later.
Think the deadline already passed?Late is not always closed. Good-cause exceptions, reopening, and external review can still be on the table. Don't assume the door is shut — that assumption is exactly what the system counts on.
Urgent care has faster, stronger rules. If waiting would seriously risk your health, you can request an expedited appeal — decided in days, not months.

One sentence to keep close: most denied claims are never appealed — and a meaningful share of the ones that are get overturned. Silence is what they expect. An appeal is not.

Don't want to do this alone?

You can fight this yourself with what's above — or have someone do it for you.

If you'd rather hand the whole thing to people who pull the records, build the medical-necessity case, and file it for you — that's exactly what YesOnUs does. It's the done-for-you version of everything on this page.

Want someone to do this for you? → YesOnUs