Cigna vs. Aetna: Employer Plans, Mental Health Coverage, and Prior Auth Compared

Cigna and Aetna are two of the major players in employer-sponsored health insurance, competing for large and mid-size group accounts across the country. Both have faced regulatory scrutiny and lawsuits in recent years. For employees evaluating these options — or fighting a denied claim — understanding how they differ in practice matters.

Corporate Overview

Cigna (now operating as The Cigna Group after its 2018 acquisition of Express Scripts) covers approximately 17 million medical customers in the United States. Its pharmacy benefit manager integration has made cost management a defining feature of its business model.

Aetna is owned by CVS Health and covers approximately 22–24 million medical members. The CVS integration gives Aetna a differentiated retail health strategy that includes pharmacy, urgent care, and MinuteClinics.

Both compete heavily in the large employer (500+ employee) and mid-market employer segments.

Prior Authorization Burden

Prior authorization is one of the clearest friction points for patients and physicians. Both Cigna and Aetna require PA for a significant portion of medical services, including specialty drugs, advanced imaging, elective procedures, and behavioral health services.

Cigna made headlines in 2023 when ProPublica published an investigation revealing that Cigna medical reviewers were using an automated system to deny PA requests in bulk — reviewers spent an average of less than two minutes per case before rejecting claims. Cigna disputed the characterization but paid a settlement related to the matter.

Aetna has faced its own PA-related lawsuits and regulatory scrutiny. In 2020, Aetna paid $17 million to California to settle allegations of improper prior authorization denials.

Both companies have since announced reductions in PA requirements for certain categories of care, partly in response to regulatory pressure and partly in anticipation of CMS rules limiting PA in Medicare Advantage.

Mental Health Parity

The Mental Health Parity and Addiction Equity Act (MHPAEA) requires insurers to cover mental health and substance use disorder services at the same level as comparable medical and surgical benefits. Both Cigna and Aetna have faced MHPAEA enforcement actions.

Cigna has been cited for:

• Applying stricter prior authorization requirements for behavioral health than for comparable medical services.
• Using more aggressive step therapy requirements (requiring less expensive treatments before approving higher-level care) for behavioral health.
• Higher Denial Rates by Insurer (2026)" class="auto-link">denial rates for residential mental health treatment.

Aetna has faced similar scrutiny:

• In 2021, a federal court found Aetna's behavioral health subsidiary improperly denied mental health and substance use disorder claims by applying internal guidelines that were more restrictive than generally accepted clinical standards.
• California's Department of Managed Health Care has cited Aetna multiple times for mental health parity violations.

For members with behavioral health needs, mental health parity rights are among the most important and most frequently violated. If your mental health or substance use treatment was denied, parity law is a powerful appeal tool.

Network Breadth and Out-of-Network Disputes

Cigna operates Open Access Plus (OAP) and LocalPlus networks with varying breadth depending on employer and geography. LocalPlus networks can be significantly narrower, limiting access to specialists.

Aetna similarly offers tiered networks including Aetna Whole Health (narrow network, high value) and traditional PPO networks. Narrow network plans generate higher denial rates for out-of-network care.

Both companies have faced disputes over:

• Balance billing by out-of-network providers.
• Emergency care denials (the No Surprises Act has changed this landscape significantly).
• Reimbursement rates for out-of-network services that left members with large bills.

Prescription Drug Coverage and Step Therapy

Both insurers use step therapy (also called fail first) protocols for expensive medications — requiring patients to try lower-cost drugs before the preferred drug is covered.

Cigna's Express Scripts integration gives it substantial control over pharmacy benefit management and formulary design. Step therapy disputes involving specialty drugs (biologics, cancer treatments, psychiatric medications) are common.

Aetna's CVS Caremark integration similarly shapes its pharmacy coverage decisions. Formulary exclusions and step therapy denials for specialty drugs are significant sources of denied claims.

Both states have step therapy override laws that give physicians the right to request exceptions for specific patients. These laws vary by state — check your state's requirements.

Appeals: What to Expect

Internal appeals at both companies must be resolved within:

• 30 days for pre-service (prior authorization) appeals.
• 60 days for post-service (paid claim) appeals.
• 72 hours for urgent/expedited appeals.

Both companies use third-party clinical reviewers for internal appeals, which sometimes produces better outcomes than the initial review. Always request the specific clinical criteria used in the denial — Cigna and Aetna use InterQual and MCG criteria that you have a right to obtain.

Fight Back With ClaimBack

Whether your employer chose Cigna or Aetna, the appeal process is similar — and the clinical criteria they use are obtainable. ClaimBack helps you build a targeted appeal that directly addresses the denial reason.

Start your appeal at ClaimBack

Related Reading

• How to Write an Insurance Appeal Letter
• What Is Medical Necessity?
• Common Reasons Insurance Claims Are Denied