Insurance companies deny claims because denials are profitable. If even 30% of denied patients simply accept the decision, the insurer saves millions. The appeal process exists because regulators know this — and it works far more often than most patients realize.
This guide walks through every step of the appeal process, from your first phone call to external review.
Step 1: Understand your denial (day 1)
Read the denial letter carefully. It must include the specific reason for denial, the clinical criteria or policy provision they used, your right to appeal and the deadline, instructions for requesting your complete claim file, and contact information for the appeals department.
If any of these elements are missing, the denial itself may be defective. Note what's missing — it strengthens your complaint.
Call the number on the denial letter. Ask for the exact clinical policy or medical necessity criteria used to deny your claim. You're legally entitled to this under the ACA. Ask them to send it to you in writing. This document is your roadmap — your appeal must address every point in it.
Step 2: Build your appeal file (days 2–14)
Your appeal needs to be a comprehensive medical argument, not just a letter saying "I disagree." Assemble:
Letter of medical necessity from your surgeon. This is the single most important document. It should directly address each point in the insurer's denial criteria, explain why the procedure is medically necessary for your specific case, reference peer-reviewed literature supporting the procedure, and describe what happens if the procedure isn't performed (disease progression, functional decline, pain).
Supporting documentation: Complete medical records showing history of the condition, documentation of all conservative treatments attempted with dates and outcomes, relevant imaging with radiologist interpretation, lab results supporting the diagnosis, functional assessments (pain scales, disability questionnaires, range-of-motion measurements), and a second surgical opinion if available.
Peer-reviewed studies: Include published studies that support the procedure for patients with your clinical profile. Your surgeon likely knows the key studies. PubMed is freely searchable if you want to find additional supporting literature.
Step 3: File the internal appeal (within deadline)
Submit your appeal in writing. Include everything — the appeal letter, your surgeon's letter of medical necessity, all supporting documentation, and a cover sheet listing every document included. Send it certified mail with return receipt so you have proof of timely filing. Many insurers also accept fax or electronic submission, but paper creates the strongest record.
The insurer must respond to a pre-service appeal within 30 days (15 days for urgent cases). Post-service appeals (the procedure already happened) have a 60-day response window.
Step 4: If internal appeal fails — external review
Under the ACA, you have the right to an independent external review after your internal appeal is denied. An independent physician — not employed by or contracted with your insurer — reviews your case. This is often a specialist in the relevant field.
External review statistics are favorable for patients. Depending on the state and procedure, 40–50% of external reviews overturn the insurer's denial. The reviewer sees the same file your insurer's medical director saw, but without the financial incentive to deny.
Your insurer must provide instructions for requesting external review in their denial of your internal appeal. The request deadline is typically 4 months from the internal appeal denial.
Step 5: State insurance department complaint
If you believe the denial or appeal process violated your state's insurance regulations, file a complaint with your state's Department of Insurance. Some violations that warrant a complaint include the insurer failing to respond within the required timeframe, not providing the clinical criteria used for denial, applying criteria that differ from what's in your policy, or misrepresenting what your plan covers.
Some states have patient advocate offices or consumer assistance programs that will intervene directly with the insurer on your behalf. Search "[your state] insurance consumer assistance" to find these resources.
What to do while you appeal
The appeal process can take weeks to months. During that time, explore parallel paths — get a cash-pay quote, research medical tourism options, check your HSA/FSA balance. If the appeal succeeds, great. If it doesn't, you'll already have your Plan B ready instead of starting from scratch.
Don't wait for the appeal outcome to start planning. The denial may stand, and the only thing worse than a denied surgery is a denied surgery plus three months of lost planning time.
Ready to explore your options?
Colombia is ranked #1 in the Western Hemisphere for healthcare quality (WHO). See what medical care costs with board-certified specialists.
Explore medical care in Colombia →Frequently asked questions
What percentage of insurance appeals are successful?
Between 40% and 60% of surgical denials are overturned at some stage of the appeal process, depending on the state, insurer, and procedure type. External reviews, handled by independent physicians, overturn denials roughly 40–50% of the time. The odds are better than most patients assume.
How long do I have to appeal an insurance denial?
Most plans require internal appeals to be filed within 180 days of the denial, though some give as few as 60 days. Check your denial letter for the specific deadline. External review requests typically must be filed within 4 months of the internal appeal denial.
What should I include in my appeal letter?
A letter of medical necessity from your surgeon addressing each point in the denial criteria, complete medical records, documentation of failed conservative treatments with dates, relevant imaging and lab results, functional assessments, peer-reviewed studies supporting the procedure, and a second surgical opinion if available.
What is an external review for insurance denial?
An external review is an independent review of your denied claim by a physician who has no financial relationship with your insurer. It's your right under the ACA after internal appeals are exhausted. The independent reviewer examines the same evidence and makes a binding or advisory determination, depending on your state.
Should I hire a lawyer for an insurance appeal?
For most first-level appeals, you can handle it yourself with your surgeon's support. If your internal and external appeals both fail and you believe the denial violates your policy or state law, consulting an insurance or health law attorney may be worthwhile. Some attorneys work on contingency for wrongful denial cases.