How to Appeal an Insurance Denial: Step by Step

An insurance denial is not the end. Roughly 40% of appealed denials are overturned — meaning nearly half the time, it's worth fighting. Here's how.

Step 1: Understand why you were denied

Your Explanation of Benefits (EOB) or denial letter must state the reason. Common reasons: - **Not medically necessary** — this is the most common and most appealable - **Not covered** — check your Summary of Benefits carefully; sometimes the denial is wrong - **Prior authorization not obtained** — this may be a provider error, not yours - **Out-of-network** — you may have grounds for exception in emergencies

Step 2: File an internal appeal

You have the right to an internal appeal with your insurance company. Do this first.

**What to include:** - A letter from your doctor explaining medical necessity (this is the most important piece) - Relevant medical records supporting the treatment - A letter from you explaining the impact of the denial on your health - Any published clinical guidelines supporting the treatment (your doctor can help with this) - The denial letter itself

**Sample appeal language:**

*"I am writing to appeal the denial of [service/medication] for account [number], denial date [date]. The denial reason cited was [reason]. I believe this decision was incorrect because [reason — e.g., this treatment meets established clinical criteria for my diagnosis of X]. Enclosed is a letter of medical necessity from my treating physician and supporting documentation."*

Step 3: File an external appeal if needed

If the internal appeal fails, you have the right to an external review by an independent organization. This is a federal right under the ACA.

• •Request external review in writing within 60 days of the internal appeal denial
• •The independent reviewer must respond within 45 days (or 72 hours for urgent situations)
• •Their decision is binding on the insurance company

Step 4: Escalate further if needed

• •Your state insurance commissioner — file a complaint if you believe your insurer is acting in bad faith
• •Your HR department — if you have employer-sponsored insurance, HR can sometimes intervene with the insurance company
• •A patient advocate — many hospitals have patient advocates on staff who can help navigate denials

Tips that matter

• •Document everything in writing
• •Keep copies of every document you send and receive
• •Follow up by phone and document those calls too
• •Meet all deadlines — they matter legally

The system is not designed to make this easy. But you have rights, and they're worth using. 💜