The Denial Letter Arrived on a Friday. She Had 180 Days to Appeal It, but Only 4 Business Days If She Asked for Expedited Review.

7 min read · Last updated September 21, 2026

A denied health insurance claim under most job-based or marketplace plans gives you 180 days to file an internal appeal, a decision within 30 to 60 days, or 4 business days if it’s urgent, and then, if denied again, 4 months to request an independent external review that must be decided within 45 days, or 72 hours for an urgent case.

In this article

• The clock nobody puts in the denial letter: 180 days to appeal
• Standard review vs. expedited: the difference is 4 business days vs. 60
• If the internal appeal fails: external review has its own separate clock
• The sequence: what to do in the first 48 hours after a denial
• Frequently asked questions

A patient in Denver got her denial letter on a Friday afternoon in September 2026, three days after a specialist recommended an MRI (magnetic resonance imaging) that the insurer’s letter called “not medically necessary.” The letter never said how long she had to fight it. The answer, buried in federal rules the insurer doesn’t have to spell out in plain language on the notice itself, was 180 days to file an appeal, and just 4 business days if her case qualified as urgent.

The clock nobody puts in the denial letter: 180 days to appeal

Under the rules that apply to most non-grandfathered job-based and Affordable Care Act (ACA) marketplace plans, HealthCare.gov states plainly that a patient must file an internal appeal “within 180 days (6 months) of receiving notice that your claim was denied.” That’s the outside deadline, not a suggestion. Missing it typically forfeits your right to the internal appeal, and to the external review that follows it. The countdown starts on the date the notice was issued, not the date you actually opened the envelope or read the portal message.

Filing something in writing before that deadline, even a short letter stating you’re appealing and why, protects your position better than waiting to assemble a perfect case first. You can supplement the appeal with more documentation afterward.

Standard review vs. expedited: the difference is 4 business days vs. 60

Once you’ve filed, your insurer has to decide within a specific window that depends on whether you’ve already received the service. For a standard appeal, HealthCare.gov specifies 30 days if the service hasn’t happened yet, or 60 days if you’ve already received it and are appealing after the fact. For an urgent case, the insurer “must come as quickly as your medical condition requires, and at least within 4 business days after your request is received.”

That 4-business-day track is not automatic. You, or your doctor acting on your behalf, have to explicitly request expedited or urgent review and explain why waiting for the standard timeline would seriously jeopardize your health, your ability to regain maximum function, or cause severe pain. A denial letter that simply says “appeal within 180 days” without you asking for expedited treatment defaults to the slower, 30-to-60-day track even on a genuinely time-sensitive case.

If the internal appeal fails: external review has its own separate clock

A second denial after the internal appeal isn’t the end of the process. HealthCare.gov’s external review page states you have “4 months after the date you receive a notice or final determination from your insurer that your claim has been denied” to request an independent external review, one conducted by a reviewer outside your insurance company entirely. A standard external review must be decided as soon as possible, and no later than 45 days after the request was received. An expedited external review must be decided no later than 72 hours, depending on the medical urgency of the case.

External review exists precisely because the insurer that denied you twice doesn’t get to be the final word. The reviewer is independent of the plan, and in most states, their decision is binding on the insurer.

The sequence: what to do in the first 48 hours after a denial

1. Read the denial notice for the exact reason given, not just the fact that it was denied. The stated reason (not medically necessary, out-of-network, missing prior authorization) determines what evidence your appeal needs to address.
2. Ask your doctor immediately whether the situation qualifies as urgent, meaning waiting for a standard decision could seriously harm your health. If yes, have your doctor submit a written statement requesting expedited review along with your appeal.
3. File the internal appeal in writing well before the 180-day deadline, even if you’re still gathering supporting records. A timely, incomplete appeal beats a complete one filed too late.
4. Track both deadlines on a calendar the moment the denial arrives: the 180-day filing window, and separately, the insurer’s own decision deadline once you’ve filed (30, 60, or 4 business days).
5. If the internal appeal is denied, request external review within 4 months of that final notice. Don’t wait to see if a second internal request changes anything first, unless your plan specifically requires exhausting a second internal step.

Step	Deadline	What happens
File internal appeal	180 days from the denial notice	You submit a written appeal to your insurer
Standard internal decision, service not yet received	30 days	Insurer must respond with a decision
Standard internal decision, service already received	60 days	Insurer must respond with a decision
Expedited internal decision	4 business days	For cases where the standard timeline would seriously jeopardize your health
Request external review	4 months after the final internal denial	An independent reviewer outside your insurer takes the case
Standard external review decision	45 days	Independent reviewer issues a binding decision
Expedited external review decision	72 hours or less	For urgent cases, based on medical urgency

This same appeal clock connects to a cost mechanic worth understanding before a denial ever happens: if your plan runs a copay accumulator or maximizer program, a specialty prescription denial can hit at the exact moment a manufacturer copay card was covering the gap, which is its own separate clock worth checking in your plan documents now, not after a denial letter arrives.

Frequently asked questions

Does the 180-day appeal window apply to every health plan? It applies to most job-based group health plans and ACA marketplace plans regulated under federal rules. Self-funded employer plans and certain grandfathered plans can differ, so check your own plan’s denial notice for its specific deadline.

What makes a case “expedited” instead of standard? Your doctor or the situation itself has to show that waiting for the standard timeline could seriously jeopardize your health, your ability to regain maximum function, or cause severe pain. You, or your doctor on your behalf, have to explicitly request expedited review. It isn’t automatic.

What happens if I miss the 180-day deadline? In most cases, missing it forfeits your right to the internal appeal and the external review that follows it. Filing something in writing before the deadline, even a brief letter, matters more than waiting to file something perfect.

Do I need a lawyer to file an appeal? No. Both internal appeals and external review are designed to be filed directly by the patient in writing, and most insurers must provide a standard appeal form. A lawyer becomes more useful only if the external review also denies the claim and you’re considering a lawsuit.

Can I request external review before finishing the internal appeal? Generally no. You typically have to exhaust the internal appeal first, though certain urgent cases and certain plans allow pursuing both at the same time. Check your specific denial letter’s instructions.