An IRO, or Independent Review Organization, is a third-party entity that reviews health insurance claim denials and decides whether your insurer was right to refuse coverage. If your health plan denies a treatment and you’ve already gone through the plan’s internal appeals process without success, an IRO gives you an outside, neutral review. Their decision is legally binding on your insurance company.
How an IRO Works
IROs employ board-certified physicians across various medical specialties to evaluate whether a denied treatment is medically necessary. These reviewers must be actively practicing doctors with no financial ties to either the insurance company or the healthcare facility involved in your case. They base their decisions on clinical expertise, current medical literature, and established treatment guidelines.
The entire point of an IRO is independence. Neither you nor your insurer chooses the specific reviewer. Federal rules require health plans to contract with at least three different IROs and rotate assignments among them, preventing any cozy relationship from developing between an insurer and a particular review organization. IROs can also earn accreditation through URAC, a nationally recognized organization that verifies they maintain fair processes, qualified reviewers, and freedom from conflicts of interest.
When You Can Request an IRO Review
You can request an external review through an IRO after your insurance company has made a final internal decision to deny your claim. Common reasons for denial include the insurer deciding a treatment isn’t medically necessary, classifying a procedure as experimental or investigational, or determining that a service falls outside your plan’s coverage terms. You have four months from the date you receive that final denial notice to file a written request for external review.
You can submit your request by mail, fax, email, or through an online portal, depending on your state’s process. You’re also allowed to send additional medical records, letters from your doctor, or other supporting information you want the reviewer to consider.
What the Review Costs You
Nothing. Federal law prohibits IROs from charging you any filing fees or costs to request an external review. The insurance company bears the cost of the process. This is an important consumer protection, since the people most likely to need an IRO review are often already dealing with expensive medical situations.
How Long the Process Takes
For a standard external review, the IRO must issue a written decision within 45 days of receiving your request. Once the review begins, your insurer has five business days to hand over all documents related to the denial.
If your situation is urgent, such as a treatment delay that could seriously jeopardize your health, you can request an expedited review. In that case, the IRO must deliver a decision within 72 hours. The initial notice can come by phone, followed by a written confirmation within 48 hours.
What Happens After the Decision
The IRO either upholds your insurer’s denial or overturns it in your favor. If the IRO decides the denied treatment is medically necessary, your insurance company is required by law to cover it. There’s no further appeal available to the insurer. This makes IRO decisions one of the strongest tools available to patients fighting a coverage denial.
If the IRO upholds the denial, your options become more limited. Depending on your state and the type of plan you have, you may be able to pursue the matter in court, but the IRO’s determination carries significant weight in any legal proceeding.
Why IROs Exist
Before external review requirements were standardized, patients whose claims were denied had few options beyond suing their insurance company, which most people couldn’t afford to do. The Affordable Care Act changed this by requiring all non-grandfathered health plans to provide access to an external review process. Plans that aren’t already subject to a state-level external review system must follow a federal process and use IROs accredited by URAC or a similar national organization.
The system was designed to level the playing field. Insurance companies have teams of medical directors making coverage decisions. An IRO gives you access to an independent physician who reviews your specific case without any incentive to deny or approve it. For treatments where medical necessity is genuinely debatable, such as newer therapies or advanced procedures like proton radiation therapy, IRO reviews can be particularly valuable. A multistate analysis published in a National Institutes of Health journal found that IROs have overturned insurance denials for proton therapy, with their decisions being legally binding on health plans to cover the treatment.
How to Strengthen Your Case
The IRO reviewer will only see what’s in the file. That means the medical records, clinical notes, and supporting documents submitted by you and your insurer are everything. Ask your treating physician to write a detailed letter explaining why the denied treatment is necessary for your specific condition, referencing clinical guidelines or published evidence when possible. Include relevant imaging, lab results, and notes showing what alternative treatments have already been tried and why they were insufficient.
Don’t assume your insurer’s submission tells your full story. You have the right to add your own documentation, and using that right can make the difference between a denial being upheld and being overturned.