The short answer
External review hands your denial to an independent organization outside the insurance company. You request it in writing within four months of the final denial notice. Standard reviews are completed within 45 days and expedited ones within 72 hours or less. Insurers are required by law to accept the result.
An independent external reviewer, not your insurer, makes the decision.
The written request must be submitted within four months of the denial notice.
Standard external reviews are completed within 45 days.
Expedited reviews are completed within 72 hours or less, depending on medical urgency.
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The full explanation.
The step where your insurer stops being the judge
Internal appeals have an obvious flaw. The company that said no is also the company checking whether no was right. External review fixes that. HealthCare.gov puts it plainly. Taking your appeal to an independent third party means your insurer no longer gets the final word on paying your claim.
This is the stage where an outsider looks at your case. The plan has to accept what they decide.
Who the reviewer actually is
There is no single national body. Depending on your state and your plan, the review goes to one of three kinds of organization:
- an independent review organization your plan hires
- an organization that takes part in your state's external review process
- an organization in the HHS-run federal external review process
You do not pick which one. Your plan and your state decide that for you. The denial notice tells you which one applies.
How to start it
Send a written request within four months of the date you get the final denial notice. That deadline is more generous than the 180 days you get for an internal appeal. But four months goes fast during treatment. Mark the date the day the denial arrives.
The contact details you need are printed on your Explanation of Benefits. You can also find them on the notice that denied your internal appeal. If you cannot find it, your state's Consumer Assistance Program can help you find the right process.
The timelines
Two numbers matter here:
- Standard review: finished within 45 days.
- Fast-track review: finished within 72 hours or less, depending on how urgent your case is.
If waiting would put your health at risk, ask for the fast track and say why. In urgent cases, you may start an external review at the same time as your internal appeal. You do not have to wait for the internal process to finish first.
Why the outcome carries weight
The decision is final. HealthCare.gov states that insurers must accept the external reviewer's decision by law. That is very different from an internal appeal, where the plan can just repeat its own answer.
Cost is low too. Plans using the HHS process charge nothing. Other processes may charge up to $25 per review.
One thing worth knowing: HealthCare.gov currently carries a notice about the four-month deadline. If your deadline to request an external review fell between July 1 and August 3, 2026, and your plan uses the HHS-administered federal process, you may be eligible for an extension until October 2, 2026. HealthCare.gov says this may apply to people in Alabama, Florida, Georgia, Texas, Wisconsin, or a US territory other than Puerto Rico, and to anyone on a state or local government plan in any state. If you think you missed the deadline in that window, ask your plan or your state's Consumer Assistance Program before assuming you are out of options.
Making your submission count
The reviewer looks at the medical question. So give them the medical facts:
- the original denial and the final internal denial notice
- a statement from your oncology team saying why the treatment fits your case
- the relevant records, including anything added to your chart after the internal appeal
- a short cover letter with your name, claim number, and insurance ID number
Did something change medically while the internal appeal was underway? New imaging, a change in your condition, a new recommendation? Make sure it is included. Reviewers decide based only on the file in front of them.
Keep the treatment question separate
An external review is a payment dispute with a deadline. What you actually need clinically is a separate talk with your care team. Ask them directly what your care plan looks like while the review is pending. Log every filing date. Keep proof of what you sent. Follow up if the 45-day or 72-hour window passes with no word.
Words to know
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Common questions
Who is the reviewer?
Depending on your state and plan, it may be an independent review organization contracted by your plan, an organization taking part in your state's external review process, or one in the HHS-administered federal external review process.
Where do I find out how to file?
The contact information appears on your Explanation of Benefits or on the notice denying your internal appeal.
Can the insurer ignore the result?
No. HealthCare.gov states that insurers are required by law to accept the external reviewer's decision, which makes it final and binding on the insurance company.
Does it cost anything?
There is no charge if your plan uses the HHS process. Other processes may charge up to $25 per review.
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Sources last checked: 2026-08-13 what this meansLast updated: 2026-08-18Next planned review: 2027-08-11
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How this page was created
Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and checked line by line against the sources listed on it. That confirms the sources support what the page says. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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