Medicare Advantage vs. Traditional Medicare: What Behavioral Health Providers Need to Know

Danielle Wagar
5 days ago
3 min read

By Danielle Wagar, CPES | Upstate Healthcare Admin

Here is a scenario that plays out in mental health practices regularly: a provider completes Medicare enrollment, receives their PTAN, and starts seeing Medicare patients. A few months in, they notice some Medicare patients have cards that say Humana, UnitedHealthcare, or Aetna. Claims are submitting to the wrong payer. Prior authorization requirements keep appearing unexpectedly. The answer is that Medicare is not one thing. Medicare Advantage (Part C) operates very differently from Traditional Medicare (Medicare Fee-for-Service).

What Is Traditional Medicare (Fee-for-Service)?

Traditional Medicare, often called Medicare Fee-for-Service (FFS) or Original Medicare, is administered directly by the federal government through CMS. Part B covers outpatient behavioral health services. When you complete Medicare enrollment through PECOS and receive your PTAN, you are enrolling to bill Traditional Medicare Part B. Claims go directly to your MAC. Reimbursement is based on the Medicare Physician Fee Schedule, set nationally by CMS. For more on the enrollment process, see our full guide on Medicare enrollment for mental health providers.

What Is Medicare Advantage (Part C)?

Medicare Advantage, also called Medicare Part C, is administered by private insurance companies that have contracted with CMS - Humana, UnitedHealthcare, Aetna, Cigna, BCBS, and others. More than half of all Medicare-eligible Americans are now enrolled in a Medicare Advantage plan.

The Critical Difference: Separate Enrollment Requirements

Enrolling in Traditional Medicare does NOT make you in-network with Medicare Advantage plans. Each MA plan has its own provider network, its own credentialing process, and its own contracts. To be in-network with a Medicare Advantage plan, you must separately apply to join that plan's network, complete that plan's credentialing process, and sign a contract with that specific plan.

Reimbursement: FFS vs. Medicare Advantage

Traditional Medicare reimbursement is set by the Medicare Physician Fee Schedule — publicly available, updated annually, non-negotiable. Medicare Advantage reimbursement is set by contract with each private insurer. Rates may be higher than FFS, lower than FFS, or indexed to FFS rates. Before contracting with any MA plan, review the proposed fee schedule carefully. For a broader look at how payers compare, see our post on NYS Medicaid rates for mental health providers.

Prior Authorization: The Biggest Operational Difference

Traditional Medicare Part B does not require prior authorization for outpatient behavioral health services in most cases.

Medicare Advantage plans frequently require prior authorization - one of the most significant operational differences. Requirements may include initial authorization, concurrent reviews, annual re-authorization, and limits on sessions per authorization. Before accepting any MA patient, confirm the prior authorization process with that specific plan.

Telehealth: Rules Differ Between FFS and MA

Traditional Medicare telehealth coverage is governed by CMS policy. Medicare Advantage plans set their own telehealth policies - an MA plan may cover telehealth services Traditional Medicare does not cover, or may impose restrictions it does not have. For billing purposes, MA telehealth claims generally use modifier 95 - see our guide on telehealth modifier 95 vs. GT for the full breakdown.

How to Tell Which Type of Medicare Your Patient Has

Traditional Medicare: Red, white, and blue Medicare card with a Medicare Beneficiary Identifier (MBI)
Medicare Advantage: Insurance card from the private insurer (Humana, Aetna, UHC, etc.) - may say Medicare Advantage or Part C

Always verify insurance type during intake and before each session.

Should You Contract With Medicare Advantage Plans?

Consider: patient access (MA enrollment is growing), administrative burden (prior auth adds workflow complexity), reimbursement rates (some MA plans pay above FFS; others pay significantly less), and contract terms (MA contracts are negotiable - review termination clauses, claims timelines, and audit rights). For providers who recently left platforms and are building their own panel, see our post on leaving Headway, Alma, or Grow Therapy.

Key Differences at a Glance

Traditional Medicare: administered by CMS, requires PECOS enrollment and PTAN, rates set by fee schedule, no prior auth for most outpatient therapy, claims go to your MAC
Medicare Advantage: administered by private insurers, requires separate contract per plan, negotiated rates, frequent prior auth requirements, claims go to the private insurer

Need help navigating Medicare or Medicare Advantage enrollment? Book a strategy session.