Insurance Denial Appeal Letter Template

[Your Name]
[Your Email Address]

June 15, 2026

[Insurance Company Name]
Appeals Department
[Insurance Company Address, City, State, ZIP Code]

Re: Appeal of Claim Denial
Policy Number: [Policy Number]
Group Number: [Group Number]
Claim Number: [Claim Number]
Date of Service: [Date of Service]
Patient: [Patient Name]
Date of Birth: [Date of Birth]

Dear Appeals Department,

I am writing to formally appeal the denial of the above-referenced claim for services provided by [Provider/Facility Name] on [Date of Service].

DENIAL REASON AND RESPONSE

Your Explanation of Benefits (EOB) states this claim was denied for the following reason:

[Insert the exact denial reason from your EOB or denial letter, e.g., "Service not medically necessary," "Prior authorization not obtained," "Out-of-network provider," etc.]

I respectfully disagree with this determination for the following reasons:

[Explain why the denied service was medically necessary and appropriate. For example: "The procedure (describe procedure) was recommended by my treating physician, Dr. [Name], based on my diagnosis of [condition]. Conservative treatments including [list prior treatments] were attempted over [time period] without adequate improvement. My physician determined that [the denied procedure] was the most appropriate next step in my care."]

LEGAL BASIS FOR THIS APPEAL

I am exercising my right to appeal under the following federal protections:

1. The Affordable Care Act (ACA), Section 2719, guarantees my right to an internal appeal and, if necessary, an independent external review of any claim denial.

2. For employer-sponsored plans, the Employee Retirement Income Security Act (ERISA), 29 U.S.C. 1133, requires that plan participants receive a full and fair review of any adverse benefit determination.

3. Your plan is required to provide a written decision on this appeal within 30 days for pre-service claims and 60 days for post-service claims.

SUPPORTING DOCUMENTATION

I am including the following documents with this appeal:

1. A copy of the Explanation of Benefits (EOB) or denial letter
2. A letter of medical necessity from my treating physician, [Provider Name]
3. Relevant medical records supporting the necessity of the service
4. Any applicable clinical guidelines or peer-reviewed literature supporting this treatment
5. Prior treatment history demonstrating that alternative approaches were attempted

REQUEST

I respectfully request that you:

1. Reverse the denial and process this claim according to my plan benefits
2. Provide a written decision within the timeframe required by law
3. If this internal appeal is denied, provide me with instructions for requesting an independent external review

If you need additional information to process this appeal, please contact me at [Your Email Address]. I expect a written response within the legally required timeframe.

Thank you for your prompt attention to this matter.

Sincerely,

[Signature]
[Your Name]

Enclosures:
- Denial letter/EOB
- Physician letter of medical necessity
- Supporting medical records
- Clinical guidelines (if applicable)

Sent via certified mail, return receipt requested