What Is a Claim Denial? (Types, Reasons, and What to Do)
Understand what a health insurance claim denial is, the most common types and reasons for denial, and the exact steps you can take to challenge and overturn it.
What Is a Claim Denial?
A claim denial is a decision by your insurance company to refuse payment for a healthcare service, prescription, or medical expense you submitted for coverage. When your insurer denies a claim, it means the company has determined — for one or more stated reasons — that it will not pay all or part of the amount billed.
A denial does not mean the decision is final. Under federal and state law, you have the right to appeal every denial, and many denials are overturned on appeal.
What Are the Types of Insurance Claim Denials?
Hard denial (absolute denial) A determination that the claim will not be paid and cannot be resubmitted as-is. Hard denials require an appeal or corrected claim to be reconsidered. Examples: service not covered under your policy, lack of medical necessity upheld after review.
Soft denial (correctable denial) A temporary denial that can be resolved by providing missing information, correcting a billing code, or resubmitting with documentation. Examples: missing Prior Authorization Denied: How to Appeal" class="auto-link">prior authorization, incorrect patient information, coordination of benefits issue.
Pre-service denial A denial issued before you receive care — typically when a prior authorization request is denied. You have the right to an expedited appeal before treatment begins.
Post-service denial A denial issued after you have already received care and the claim has been submitted for payment.
Concurrent review denial A denial issued during an ongoing hospitalization or course of treatment, terminating coverage for future care.
Retroactive denial A denial of a claim that was previously paid, in which the insurer attempts to recoup payment from your provider.
What Are the Most Common Reasons for Claim Denial?
1. Medical necessity The insurer determines that the treatment was not medically necessary based on its internal clinical criteria. This is the most commonly appealed denial reason.
2. Lack of prior authorization The service required advance approval from the insurer and either no authorization was obtained or the wrong procedure was authorized.
3. Out-of-network provider You received care from a provider not in your plan's network, and your plan does not cover out-of-network services (except for emergencies, which have separate protections).
4. Coverage exclusion The service is specifically excluded from your policy — for example, certain cosmetic procedures, experimental treatments, or services the plan does not cover.
5. Coordination of benefits If you have more than one insurance plan, one insurer may deny a claim stating the other plan should pay first.
6. Billing and coding errors Incorrect CPT codes, ICD-10 diagnosis codes, or provider identification numbers can trigger a denial that has nothing to do with your medical situation.
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7. Timely filing deadline missed Most insurers require claims to be submitted within a set period (often 90 to 180 days) after the service date. Late submissions may be denied.
8. Experimental or investigational treatment The insurer classifies your treatment as experimental and therefore not covered, even if your physician considers it standard of care.
9. Duplicate claim The claim was submitted more than once for the same service.
10. Eligibility issues The insurer cannot confirm you were enrolled and covered at the time of service.
What Should You Do When a Claim Is Denied?
Step 1: Read the denial notice carefully. Your EOB)" class="auto-link">Explanation of Benefits (EOB) or denial letter must state the reason for denial in plain language, cite the specific policy provision or criteria used, and explain how to appeal.
Step 2: Determine the denial type. Is it a soft denial you can correct by resubmitting with documentation? Or a hard denial requiring a formal appeal?
Step 3: Gather your evidence. Collect medical records, your physician's letter of medical necessity, clinical guidelines supporting your treatment, and any prior communications with the insurer.
Step 4: File an internal appeal. Submit a written appeal to your insurer within the required timeframe — typically 180 days from the denial notice under ACA rules, though ERISA plans may have shorter windows as low as 60 days.
Step 5: Request an External Independent Review: Complete Guide" class="auto-link">external review if needed. If your internal appeal is denied, you have the right to an independent external review by a neutral third-party organization. External reviews overturn insurer decisions in 30–60% of cases.
Step 6: File regulatory complaints if appropriate. You can file a complaint with your state insurance commissioner, the Department of Labor (for ERISA plans), or CMS (for Medicare/Medicaid issues) at any time.
What Deadlines Apply to Claim Denial Appeals?
- ACA-compliant plans: 180 days to file an internal appeal from the denial notice
- ERISA plans: Often 60–180 days — check your Summary Plan Description
- Medicare: 120 days to file an appeal for Part A/B; 60 days for Medicare Advantage
- Medicaid: 90 days in most states
- External review: 4 months (120 days) from final internal denial under federal rules
Missing these deadlines can forfeit your right to appeal, so act promptly.
Can a Claim Denial Be Overturned?
Yes — regularly. Studies show that the majority of insured Americans who appeal a claim denial receive at least partial reversal. The key is submitting a well-documented, evidence-based appeal that directly addresses the insurer's stated reason for denial.
Fight Back With ClaimBack
A claim denial is not the end of the road. ClaimBack helps you draft a professional, compelling appeal that addresses your insurer's specific denial reason with the right evidence and legal language.
Start your appeal at https://claimback.app/appeal.
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