The Clock Starts the Day You're Denied: What Every Insurance Appeal Deadline Actually Means

You open the letter, you read the word "denied," and the paperwork goes in a drawer. That drawer is where most appeals go to die — not because the denial was correct, but because the deadline quietly passed.

Here is what the letter does not put in bold: the moment you are denied, a clock starts. And it is shorter than you think.

Why the deadline matters more than the denial

In 2023, insurers issued roughly 73 million claim denials in the ACA marketplace. Fewer than 1% were ever appealed (KFF). Not because patients agreed with the decision — because the window closed before anyone acted.

When patients do appeal, the odds shift dramatically. On Medicare Advantage appeals, 82% of denials were overturned (Stanford/KFF). The single biggest thing standing between you and that overturn is a date.

The deadlines you need to know

Your exact timeline depends on your plan type, so check your denial letter and plan documents first. In general:

Internal appeal: Most plans give you a set number of days from the date on the denial letter to file an internal appeal. This is the first ask — you're asking the insurer to review its own decision.

External review: If the internal appeal is denied, you can usually request an independent external review. This has its own separate deadline, which starts after the internal decision.

Urgent situations: If a delay could seriously jeopardize your health, expedited timelines exist that move much faster.

The dates are printed in your denial letter and your Summary of Benefits. If you cannot find them, your plan is required to tell you.

What to do the day the letter arrives

Write down the date on the letter — not the date you opened it.

Find the appeal deadline in the letter or plan documents.

Request your full claim file and the specific reason for denial in writing.

Start your appeal before the drawer wins.

Ellen tracks these deadlines for you, so a missed date never decides your care.

Ellen does not provide medical advice. This information is educational and is not a substitute for guidance from your healthcare provider or a review of your own plan documents.