If your health insurer denied your surgery, you have the right to challenge the decision, and the law gives you a defined path to do it. Knowing what to do when insurance denies surgery comes down to working through the layers in order: read the denial, fix anything that can be fixed quickly, ask your doctor to call the insurer directly, then file a formal internal appeal, and if that fails, request an independent external review. Each step has its own deadline, and missing one can end your case before it’s really started.
Start With the Denial Letter
Every insurer must send you a written explanation when it denies a claim. That letter has to state the specific reason, cite the plan language or exclusion the insurer relied on, and tell you how to appeal and by when.1Office of the Law Revision Counsel. 29 USC 1133 Claims Procedure Read it closely before doing anything else. The reason the insurer gives determines your next move.
Some denials are clinical disagreements: the reviewer decided the surgery isn’t medically necessary, or the procedure is considered experimental. Those require a formal appeal with clinical evidence. But a surprising number of denials come from billing or coding mistakes — a wrong diagnosis code, a mismatched procedure code, or a missing modifier. If your surgeon’s office submitted the claim with an incorrect CPT or ICD-10 code, the fix can be as simple as having the billing department resubmit with corrected codes. Call your provider’s billing office and ask them to verify the codes match the procedure your doctor recommended. One phone call can resolve the problem without any appeal at all.
If the denial is based on medical necessity, an exclusion, or an out-of-network determination, start gathering your medical records, test results, and any clinical notes from your surgeon that explain why the procedure is needed.
Ask Your Doctor for a Peer-to-Peer Review
Before filing a written appeal, ask your surgeon or treating physician to request a peer-to-peer review with the insurer’s medical director. This is a phone conversation where your doctor explains directly to the insurer’s physician why the surgery is medically necessary. A successful peer-to-peer can overturn the denial on the spot and save you weeks of paperwork.
Insurers don’t always make this easy. Some limit the window for scheduling the call or make it hard for your doctor to reach the right reviewer, and some physicians decline to participate because the process is uncompensated. It’s still worth asking, especially in clear-cut cases where the clinical evidence is strong. If peer-to-peer doesn’t work or isn’t offered, move to a formal internal appeal.
File an Internal Appeal
An internal appeal is your formal request asking the insurer to reconsider. You have 180 days from the date you received the denial notice to file.2HealthCare.gov. Internal Appeals Miss that window and you lose the right to challenge the decision through the insurer. Mark the deadline immediately.
Your appeal should be a written letter that references the denial, identifies the specific reason the insurer gave, and explains why you disagree. The strongest appeals include:
- A letter of medical necessity from your surgeon explaining the diagnosis, why conservative treatments have failed or aren’t appropriate, and what clinical guidelines support the procedure.
- Relevant medical records and test results, including imaging, lab work, and specialist evaluations.
- Published clinical evidence, such as peer-reviewed studies or professional society guidelines showing the surgery is standard of care for your condition.
- The insurer’s own coverage policy. If the plan’s medical policy for the procedure lists criteria you meet, point that out explicitly.
Your doctor’s letter is the single most important piece. A vague one-liner won’t do. The letter needs to connect your specific clinical situation to the criteria the insurer uses, and it should explain why alternatives won’t work and what happens if the surgery is delayed.
How Long the Insurer Has to Respond
The insurer must complete its review within 30 days for a surgery you haven’t had yet, and within 60 days for a surgery already performed.2HealthCare.gov. Internal Appeals For urgent situations where waiting could seriously jeopardize your health, you can request an expedited review, and the insurer must decide within 72 hours.
If the Insurer Misses Its Deadline
If your insurer blows past the response deadline or fails to follow the required appeals procedures, federal regulations treat the internal appeals process as “deemed exhausted.” You can skip straight to an external review, or for employer-sponsored plans governed by ERISA, pursue legal remedies without waiting for the insurer to finish.3eCFR. 45 CFR 147.136 – Internal Claims and Appeals and External Review Processes If this happens, request a written explanation from the insurer within 10 days describing why it missed the deadline. That documentation strengthens your position later.
Request an External Review
If the internal appeal fails, you have the right to an external review: an independent evaluation by a reviewer with no connection to your insurance company. This is where many denials get overturned, because the decision-maker has no financial stake. All non-grandfathered health plans (most plans created or significantly modified after March 23, 2010) must offer this process under the Affordable Care Act.4Centers for Medicare & Medicaid Services. HHS-Administered Federal External Review Process for Health Insurance Coverage
You must file a written request for external review within four months of receiving your final internal appeal denial.5HealthCare.gov. External Review Include your original denial letter, all internal appeal documents, and any new medical evidence you’ve gathered. The independent review organization must issue a decision within 45 days for standard reviews.4Centers for Medicare & Medicaid Services. HHS-Administered Federal External Review Process for Health Insurance Coverage For urgent cases, an expedited review can be completed within 72 hours.6U.S. Department of Health and Human Services. Internal Claims and Appeals and the External Review Process
The reviewer’s decision is binding on both you and the insurer.4Centers for Medicare & Medicaid Services. HHS-Administered Federal External Review Process for Health Insurance Coverage If the reviewer sides with you, the insurer must cover the surgery. Some states charge a small administrative filing fee (typically $25 or less); others charge nothing.
What External Review Doesn’t Cover
Not every denial qualifies. External review applies to disputes about medical necessity, experimental treatment classifications, and similar clinical questions. If your denial was based on eligibility — the insurer says you weren’t enrolled or don’t meet a waiting period — that’s not eligible for external review.3eCFR. 45 CFR 147.136 – Internal Claims and Appeals and External Review Processes Eligibility disputes follow a different path, usually through the plan administrator or, for employer plans, the Department of Labor.
If the Denial Involves an Out-of-Network Provider
If your surgery was denied or your bill inflated because a provider involved was out-of-network, even though you went to an in-network hospital, the No Surprises Act may protect you. The law prohibits out-of-network balance billing for most emergency services and for non-emergency services performed by out-of-network providers at in-network facilities.7Centers for Medicare & Medicaid Services. No Surprises Understand Your Rights Against Surprise Medical Bills This covers the situations that catch surgical patients off guard: an out-of-network anesthesiologist or assistant surgeon assigned to your case at a hospital that’s in your plan’s network.
Under these protections, you can’t be charged more than your in-network cost-sharing amount. If you receive a bill that violates this, contact your insurer and reference the No Surprises Act. The law also set up a dispute resolution process between providers and insurers that keeps the patient out of the middle.
File a Complaint With Your State Insurance Department
While you pursue appeals, you can also file a complaint with your state’s department of insurance. Every state has one, and they investigate whether insurers are following state and federal law. If your insurer broke its own rules, missed deadlines, or applied a policy incorrectly, the department can intervene. For marketplace plans, individual plans, and most state government employee plans, the state insurance department has regulatory authority.
There are limits. Most state insurance departments cannot override a medical necessity determination or order the insurer to pay for a specific surgery. Their role is regulatory. For self-insured employer plans (common at large companies), the state department typically lacks jurisdiction, and complaints go to the Department of Labor’s Employee Benefits Security Administration instead.
Some states fund Consumer Assistance Programs that provide free, direct help with insurance problems by phone, email, or in person. These programs can help you draft appeal letters, understand your rights, and navigate the process.8Centers for Medicare & Medicaid Services. Consumer Assistance Program
Legal Action as a Last Resort
If your appeals are exhausted and the external reviewer sided with the insurer, litigation is technically available, but the practical options depend on what kind of plan you have.
Most employer-sponsored health plans are governed by ERISA. ERISA allows you to sue to recover the benefits you were denied, and courts can award attorney’s fees.9Office of the Law Revision Counsel. 29 USC 1132 – Civil Enforcement But the remedies are narrow. Under ERISA, you generally cannot recover punitive damages, emotional distress damages, or get a jury trial. The court reviews the plan’s decision, often under a deferential standard, and either upholds or reverses it. If you win, you get the surgery covered, but not additional compensation for the delay or stress.
Plans that aren’t governed by ERISA, like individual marketplace plans or state government employee plans, may allow broader remedies under state law, including bad-faith insurance claims. These cases can be worth more but are also fact-intensive and expensive. Consult a health insurance attorney before filing suit. Many offer free consultations, and the strength of your case often depends on how well you documented the appeal process.
If You Still Need to Pay for the Surgery
Sometimes appeals don’t produce the result you need, or you need the surgery too urgently to wait. Every nonprofit hospital in the United States holding tax-exempt status under Section 501(c)(3) is required by federal law to maintain a written financial assistance policy that describes eligibility criteria, available discounts and free care, how to apply, and how charges are calculated.10eCFR. 26 CFR 1.501(r)-4 – Financial Assistance Policy and Emergency Medical Care Policy Eligibility is usually based on household income relative to the federal poverty level. Hospitals must publicize these policies, but they rarely advertise them aggressively. You almost always have to ask.
Contact the hospital’s financial counseling or billing department before your surgery if possible. Ask for a copy of the financial assistance policy and the application form. The hospital cannot deny you financial assistance for failing to provide documents that aren’t listed in the policy or application. Even hospitals that aren’t nonprofit will often negotiate a lower cash-pay price or offer interest-free payment plans. Ask for an itemized bill so you can identify charges that look inflated or duplicated.