Free Research Tool

How Each Insurer
Denies Claims

HealthCare.gov insurers denied 19% of in-network claims in 2024, but fewer than 1% of those denied claims were formally appealed. KFF data shows medical necessity was only 5% of reported in-network denial reasons — documentation and plan rules are usually where appeals win.

19%

Of 2024 ACA marketplace in-network claims denied (KFF)

<1%

Of denied ACA Marketplace in-network claims are formally appealed (KFF)

23

US insurers, pharmacy benefit managers, and public programs with denial-pattern playbooks

Source: KFF, Claims Denials and Appeals in ACA Marketplace Plans in 2024. The playbook count is Lysco’s own. Rates are aggregate averages — individual results vary based on denial type, insurer, and documentation.

Playbooks

Pick your insurer.

Denial patterns, appeal strategies, points to check — researched per payer.

UnitedHealthcare

EmployerIndividualMedicare Advantage+1

4 known denial patterns

Response: 30 days (internal), 45 days (external)

Anthem Blue Cross Blue Shield

EmployerIndividualMedicare Advantage+1

4 known denial patterns

Response: 30 days (internal), 45 days (external)

Aetna (CVS Health)

EmployerIndividualMedicare Advantage+1

4 known denial patterns

Response: 30 days (internal), 45 days (external)

Cigna Healthcare

EmployerIndividualMedicare Advantage

4 known denial patterns

Response: 30 days (internal), 45 days (external)

Humana

Medicare AdvantageEmployerIndividual+1

4 known denial patterns

Response: 30 days (internal for MA), standard CMS timelines

Kaiser Permanente

HMOMedicare AdvantageMedicaid

4 known denial patterns

Response: 30 days (internal), 45 days (external)

Centene / WellCare / Ambetter

MedicaidMedicare AdvantageACA Marketplace+1

4 known denial patterns

Response: 30 days (internal), varies by state for fair hearings

Molina Healthcare

MedicaidMedicare AdvantageACA Marketplace

4 known denial patterns

Response: 30 days (internal), varies by state

Blue Cross Blue Shield Federal Employee Program (FEP)

Federal Employee

4 known denial patterns

Response: 30 days (plan level), 45-60 days (OPM)

Highmark Blue Cross Blue Shield

EmployerIndividualMedicare Advantage+1

4 known denial patterns

Response: 30 days (internal), 45 days (external)

Oscar Health

IndividualACA MarketplaceSmall Group

4 known denial patterns

Response: 30 days (internal), 45 days (external)

Independence Blue Cross

EmployerIndividualMedicare Advantage+1

4 known denial patterns

Response: 30 days (internal), 45 days (external)

CareFirst BlueCross BlueShield

EmployerIndividualMedicare Advantage

4 known denial patterns

Response: 30 days (internal), 45 days (external)

Blue Cross Blue Shield of California (Anthem Blue Cross)

EmployerIndividualACA Marketplace+2

4 known denial patterns

Response: 30 days (internal), 45 days (DMHC IMR)

Blue Cross Blue Shield of Illinois

EmployerIndividualACA Marketplace+2

4 known denial patterns

Response: 30 days (internal), 45 days (external review)

Blue Cross Blue Shield of Texas

EmployerIndividualACA Marketplace+2

4 known denial patterns

Response: 30 days (internal), 45 days (IRO review)

Florida Blue (Blue Cross Blue Shield of Florida)

EmployerIndividualACA Marketplace+1

4 known denial patterns

Response: 30 days (internal), 45 days (external review)

Blue Cross Blue Shield of Michigan

EmployerIndividualACA Marketplace+2

4 known denial patterns

Response: 30 days (internal), 45 days (external review)

Medicare Fee-for-Service (Traditional Medicare)

Medicare Part AMedicare Part BMedicare Part D

5 known denial patterns

Response: 60 days (redetermination), 60 days (reconsideration), 90 days (ALJ)

CVS Caremark (Pharmacy Benefit Manager)

Pharmacy Benefit (employer)Medicare Part DMedicaid Pharmacy+1

4 known denial patterns

Response: Part D: exception or coverage request 72h standard / 24h expedited; redetermination 7 days standard / 72h expedited / 14 days for payment; 30 days (commercial)

Express Scripts (Pharmacy Benefit Manager)

Pharmacy Benefit (employer)Medicare Part DMedicaid Pharmacy+1

4 known denial patterns

Response: Part D: exception or coverage request 72h standard / 24h expedited; redetermination 7 days standard / 72h expedited / 14 days for payment; 30 days (commercial)

OptumRx (Pharmacy Benefit Manager)

Pharmacy Benefit (employer)Medicare Part DMedicaid Pharmacy+1

4 known denial patterns

Response: Part D: exception or coverage request 72h standard / 24h expedited; redetermination 7 days standard / 72h expedited / 14 days for payment; 30 days (commercial)

Medicaid (State Medicaid Program — Generic Template)

Medicaid Fee-for-ServiceMedicaid Managed CareCHIP

5 known denial patterns

Response: 30-45 days (MCO internal), 90 days (state fair hearing)

Categories

Why claims get denied.

The most common reasons insurers say no — and what each one really means for your appeal.

Medical Necessity

Service deemed not medically necessary

Experimental/Investigational

Treatment considered experimental

Out of Network

Provider not in plan network

Prior Authorization

Required prior authorization not obtained

Not Covered

Service not covered under plan

Timely Filing

Claim filed past deadline

Duplicate Claim

Claim considered a duplicate

Coding Error

CPT/ICD coding mismatch

Incomplete Documentation

Missing required documentation

Formulary

Drug not on formulary

Step Therapy

Must try other treatments first

Benefit Exclusion

Explicitly excluded by plan

Coordination of Benefits

Other insurance should pay

Administrative

Administrative/procedural issue

Have a denial? Upload it for free analysis.

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This is general guidance compiled by Lysco. Check it against your plan documents and the notice you received, which set the rules for your appeal. It does not constitute legal, medical, or financial advice. Individual results vary. Statistics are industry averages and do not represent Lysco-specific outcomes.