What Is Medicare Advantage?
Medicare Advantage (Part C) is private health-plan coverage that replaces Original Medicare Parts A and B, offered by insurers under contract with CMS, typically as HMO or PPO products with provider networks, prior-authorization, and capitated risk-adjusted CMS payments.
- Practices should verify MA enrollment at every visit, maintain a payer-ID mapping for the major MA plans in their region, and track MA-specific denial patterns separately from Original Medicare.
- Building MA-specific prior-auth workflows is essential for orthopedics, oncology, cardiology, and any specialty with high-cost imaging or procedures.
Medicare Advantage
Also known as: MA; Medicare Part C; MA Plans
Medicare Advantage (Part C) is private health-plan coverage that replaces Original Medicare Parts A and B, offered by insurers under contract with CMS, typically as HMO or PPO products with provider networks, prior-authorization, and capitated risk-adjusted CMS payments.
Definition
Medicare Advantage plans are paid a risk-adjusted per-member-per-month (PMPM) capitation by CMS based on member HCC scores, then bear financial risk for member care. Major MA insurers include UnitedHealthcare, Humana, CVS/Aetna, Elevance, and Kaiser Permanente. As of 2024, more than 50% of Medicare-eligible beneficiaries are enrolled in MA. MA plans must cover all Original Medicare benefits but can add supplemental benefits (vision, dental, OTC) and impose network and prior-authorization requirements that Original Medicare does not. Claims go directly to the MA plan, not to a Medicare MAC.
Example
A patient enrolled in Humana Medicare Advantage HMO must use Humana's network and obtain prior authorization for advanced imaging (MRI) or specialty referrals. Submitting a claim to Original Medicare for this patient returns a 'Medicare Advantage enrollment' rejection — the claim must be rebilled to Humana with the correct payer ID.
Common Misconceptions
MA plans are often perceived as 'easier' than Original Medicare because of marketing, but for billing they are typically harder due to prior-authorization, network restrictions, downcoding, and aggressive denial patterns. MA plans deny a substantially higher percentage of prior-auth requests than Original Medicare denies coverage requests, per OIG and KFF analyses.
Practical Application
Practices should verify MA enrollment at every visit, maintain a payer-ID mapping for the major MA plans in their region, and track MA-specific denial patterns separately from Original Medicare. Building MA-specific prior-auth workflows is essential for orthopedics, oncology, cardiology, and any specialty with high-cost imaging or procedures.
Related Terms
Medicare Part A/B/C/D
Medicare is divided into four parts: Part A covers hospital inpatient, SNF, hospice, and home health; Part B covers physician services and outpatient care; Part C (Medicare Advantage) is private plans replacing A and B; Part D covers prescription drugs.
Read definition arrow_forwardCMS
CMS is the federal agency within the U.S. Department of Health and Human Services that administers Medicare, jointly administers Medicaid and CHIP with the states, and oversees the Health Insurance Marketplaces and HIPAA administrative simplification.
Read definition arrow_forwardPrior Authorization
Prior authorization is the payer's process of pre-approving a planned service, procedure, medication, or admission before it is rendered, based on medical-necessity criteria; without an approved PA where required, claims typically deny under CARC 197.
Read definition arrow_forwardCommercial Payer
A commercial payer is a private (non-government) insurance company offering health coverage to individuals or employer groups, typically as PPO, HMO, EPO, or POS products under state insurance department regulation and ERISA for self-funded plans.
Read definition arrow_forwardWhere This Applies on MedPrecision
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