8.1 Medicare Advantage (Part C)

Medicare Advantage (Part C) Overview

Medicare Advantage (MA), also called Medicare Part C, is an alternative way to receive Medicare benefits. Instead of getting Part A (hospital) and Part B (medical) through the federal government, beneficiaries enroll in a private, Medicare-approved health plan that bundles both. MA plans are administered by private insurers under contract with CMS and must follow strict coverage and consumer-protection rules.

Quick Answer: MA = Part A + Part B delivered through a private plan (HMO, PPO, PFFS, SNP, or MSA). Plans must cover all Part A/B services, must include an annual out-of-pocket maximum, and may bundle Part D drugs and extras like dental, vision, and fitness.

How MA Differs from Original Medicare

MA Plan Types

1. Health Maintenance Organization (HMO) — beneficiaries use in-network providers; referrals are often required for specialists; out-of-network care is generally covered only in emergencies.
2. Preferred Provider Organization (PPO) — in-network providers are preferred, but members may go out-of-network at higher cost sharing; no referrals required.
3. Private Fee-for-Service (PFFS) — the plan decides allowable charges; no provider network is required, but providers must accept the plan's terms.
4. Special Needs Plans (SNPs) — restricted to targeted populations (see below).
5. Medicare Medical Savings Account (MSA) — a high-deductible health plan paired with a savings account the plan funds; the beneficiary pays all costs until the deductible is met.

Special Needs Plans (SNPs)

SNPs limit enrollment to beneficiaries with special needs and tailor benefits to that group:

• Dual-eligible SNP (D-SNP) — people eligible for both Medicare and Medicaid.
• Chronic condition SNP (C-SNP) — people with severe chronic conditions such as diabetes, heart failure, ESRD, or COPD.
• Institutional SNP (I-SNP) — residents of nursing homes or those requiring institutional-level care.

Coverage Requirements and MOOP

MA plans must cover all Part A and Part B services. They may charge different cost sharing than Original Medicare, but they must include an annual maximum out-of-pocket (MOOP). CMS sets a maximum allowable MOOP each year; plans may offer lower MOOPs to compete. Once a beneficiary hits the in-network MOOP, the plan pays 100% of covered services for the rest of the year. Out-of-network MOOP may be higher or unlimited in some PPOs, which is why beneficiaries with providers outside a PPO network should compare the in-network and out-of-network caps carefully before enrolling.

Network Rules and Referrals

Network rules differ by plan type. HMO plans generally require the beneficiary to select a primary care physician (PCP) and obtain referrals before seeing specialists, and out-of-network non-emergency care is usually not covered. PPO plans give members more freedom to use out-of-network providers at a higher cost sharing level, with no referrals required. PFFS plans have no network at all. SNPs typically use tailored, coordinated networks that include specialists relevant to the population they serve, and they often integrate Medicare and Medicaid benefits for D-SNP members. MSA plans pair a high deductible with a network or allow any Medicare provider, depending on the plan's design.

Extra Benefits and MAPD

MA plans frequently add benefits that Original Medicare lacks — routine dental, vision, hearing aids, wellness programs, and gym memberships. These extras are funded partly through rebate dollars the plan receives from CMS when it bids below the benchmark. A Medicare Advantage Prescription Drug (MAPD) plan bundles Part D drug coverage into the MA plan. If a beneficiary joins an MA plan without drug coverage (an MA-only plan), they generally must enroll in a standalone Part D PDP to avoid the late enrollment penalty.

Enrollment and Disenrollment

To join an MA plan, a person must be enrolled in both Part A and Part B and live in the plan's service area. Most beneficiaries enroll during the Annual Enrollment Period (AEP, October 15–December 7), with coverage starting January 1. The Open Enrollment Period (January 1–March 31) allows one switch between MA plans or a return to Original Medicare plus Part D. The Medicare Advantage Disenrollment Period (MADP, January 1–February 14) historically allowed leaving an MA plan to return to Original Medicare; since 2019 it has been folded into the broader Open Enrollment Period, though exams may still reference MADP by name.

Key Exam Pointers

• MA plans replace Original Medicare Part A/B; beneficiaries are still in Medicare and must keep paying Part B premiums.
• MA cannot charge higher cost sharing than Original Medicare for certain services such as hospice, clinical trials, and dialysis.
• SNPs are the only MA plans that may restrict enrollment based on a beneficiary's health condition.
• PFFS plans do not require networks; HMOs generally do not cover out-of-network non-emergency care.
• Because MA already includes an out-of-pocket cap, beneficiaries cannot use a Medigap policy with MA.