What to do when insurance denies your claim

Request a written explanation of the denial — insurers are required to provide one. Review the denial reason carefully, then contact your doctor's office. They can often submit a peer-to-peer review or letter of medical necessity that overturns the denial without a formal appeal.

A prior authorization denial means your insurer refused to pre-approve a treatment your doctor ordered. You have the right to appeal. Ask your doctor to submit a letter of medical necessity citing clinical guidelines (such as NCCN or AHA). If the internal appeal fails, you can request an Independent Medical Review (IMR) or External Review — a neutral third party that overturns insurer decisions roughly 40% of the time.

Step therapy (also called "fail first") requires you to try cheaper treatments before your insurer will cover the one your doctor prescribed. You can request a step therapy exception if the required drugs are contraindicated, you've already tried them, or your condition requires immediate treatment. Ask your doctor to document the medical necessity for skipping the required steps.

Most insurers require you to file an internal appeal within 180 days of receiving the denial notice. For urgent or ongoing care, you may be entitled to an expedited appeal decision within 72 hours. After exhausting internal appeals, you typically have 4 months to request an external review. These timelines can vary by plan type (employer-sponsored, marketplace, Medicare Advantage, Medicaid) and by state, so check your denial letter for your plan's specific deadlines.

An external review is an independent evaluation of your insurer's decision by a certified, neutral organization — not the insurance company. Under the ACA, most plans must offer external review. To request one, contact your state insurance commissioner or use the federal external review process at healthcare.gov. There is usually no cost to you.

Yes — and their involvement significantly improves your odds. Ask your doctor to submit a peer-to-peer review (a direct call between your doctor and the insurer's medical reviewer), a letter of medical necessity, or supporting clinical literature. Many denials are overturned at this stage before a formal appeal is even filed.

Delays are a common tactic. Document every interaction — dates, names, and what was said. File a formal complaint with your state insurance commissioner. Under CMS rules effective January 1, 2026, most federally regulated health plans must issue expedited prior-authorization decisions within 72 hours and standard decisions within 7 calendar days; if your plan is subject to these rules and is missing those deadlines, cite them in your complaint. You can also contact your employer's HR department if you have employer-sponsored insurance — they have leverage with the insurer. Note: these federal timelines apply to prior authorization requests, not to claim appeals; appeal deadlines are governed by separate rules.

A retroactive denial is when an insurer approves care upfront but later denies the claim after treatment is complete. These are often challenged successfully. File an internal appeal immediately, have your doctor document that the care was medically necessary, and request an external review if the internal appeal fails. Many states have laws specifically restricting retroactive denials.

Yes — and it happens frequently. Insurers can deny care they deem not medically necessary, experimental, or outside your plan's coverage. However, you have the right to appeal and to have your case reviewed by an independent medical expert. If the denial involves an urgent medical situation, request an expedited appeal and contact your state insurance commissioner.

Under the ACA and most state laws, you have the right to: a written explanation of any denial; an internal appeal reviewed by someone not involved in the original decision; an expedited appeal for urgent care; an independent external review; and to continue receiving care while an appeal is pending in some circumstances. You also have the right to file a complaint with your state insurance commissioner at no cost.

The No Surprises Act (effective 2022) protects patients from unexpected out-of-network bills in emergency situations and from surprise bills from out-of-network providers at in-network facilities. It does not cover all denial situations, but if you received emergency care or care at an in-network facility and received a large out-of-network bill, you may have protections under this law.

For complex denials — especially those involving large bills, experimental treatments, or repeated appeals — a patient advocate or healthcare attorney can be valuable. Many patient advocates work on contingency (no upfront cost). Your state may also have a free State Health Insurance Assistance Program (SHIP) that provides counseling for Medicare beneficiaries.