Insurers deny about 1 in 5 claims. Fewer than 1 in 100 people fight back — but when they do, they win roughly 40–50% of the time. Here's how to be one of them.
Don't pay it yet.
A denial is not a final bill. Call the provider and ask them to pause the account because the claim is under appeal.
Find your denial code.
On your Explanation of Benefits (the "not a bill" letter), look for "reason code" or "CO-## / PR-##."
Write down your deadline (see the box below).
Miss it and the denial stands — no matter how strong your case.
Appeal.
It's free and it's your legal right. Your doctor's notes are usually your best evidence.
If they say no again, keep climbing.
Independent external review comes next — a doctor who doesn't work for your insurer decides.
⏰ Your deadline to appeal — from the date on the denial:
Job or Marketplace plan: 180 days
Original Medicare: 120 days · Medicaid: about 90 days
Medicare Advantage: only 65 days — and urgent care can be faster
Free human help, too:
Your State Health Insurance Assistance Program (SHIP): 1-877-839-2675 · Your state's Consumer Assistance Program and insurance commissioner · The hospital's financial-assistance office (nonprofit hospitals are required to have one).
Free tool: decode your denial & draft your appeal at appealclock.com
AppealClock is a free, independent tool — not affiliated with any insurer or government agency. It stores no medical information. Not legal or medical advice.