How to Appeal a Denied Health Insurance Claim (and the 180-Day Clock)

Your insurer denied the claim. The letter is vague, it uses words like "not medically necessary," and nowhere does it say what happens next. That silence is doing a lot of work.

You have a legal right to appeal, and the clock on that right is already running.

The deadline nobody puts in the letter

You have 180 days - six months - from the date you receive notice that your claim was denied to file an internal appeal. Miss it and you generally lose the right, no matter how wrong the denial was.

That is the single most important number on this page, and it is the one most people learn about too late.

What a denial is supposed to look like

Before any of this, your insurer owes you a written explanation, and the law puts a clock on that too:

• Within 15 days if you were seeking prior authorization for a treatment
• Within 30 days for medical services you have already received
• Within 72 hours for urgent care cases

If you got a denial with no written explanation, that is itself a problem worth writing down.

Step one: the internal appeal

An internal appeal is you formally asking the insurance company to reconsider. The same company. That is not a flaw in the design, it is the design - the law requires them to look again with fresh eyes before anyone independent gets involved.

To file one you complete whatever forms your insurer requires, or write to them directly, and include the documents that support you. A letter from your doctor explaining why the care was necessary is the single most useful thing you can attach.

Once you file, the company is on a clock:

• 30 days to complete the appeal if it is for a service you have not received yet
• 60 days to complete it if it is for a service you have already received

At the end, they must give you their decision in writing.

If the timeline itself is the danger

You can file an expedited appeal if waiting for the standard process would seriously jeopardize your life or your ability to regain maximum function.

And in urgent situations you can request an external review at the same time as the internal appeal, without waiting to finish the internal process first. Most people do not know that is allowed.

Step two: the external review

If the internal appeal fails, you have the right to take it to an independent third party. This is the part that changes the math, because the insurer is no longer the one deciding.

You must file a written request for external review within 4 months after the date you receive the final determination from your insurer.

An independent reviewer then issues a final decision. The insurance company is required to accept it.

Free help exists and almost nobody uses it

The Consumer Assistance Program in your state can file an appeal on your behalf. Not advise you on it - file it. That service costs nothing and it is written into the federal process.

The four dates to write on the denial letter right now

Before you put that envelope down, write these on it:

1. The date you received the denial
2. That date plus 180 days - your internal appeal deadline
3. The date of the final determination, when it comes
4. That date plus 4 months - your external review deadline

Those four dates are the whole system. Everything else is paperwork.