Medicare Advantage in the Landscape

For most of its history, Medicare Advantage was the alternative: the private option a minority of beneficiaries chose instead of traditional Medicare. That framing is now out of date, and the shift matters for everything else in this course.

The scale

About 55 percent of eligible Medicare beneficiaries are enrolled in Medicare Advantage in 2026, just over 35 million people. A majority of the Medicare population is now covered by private plans rather than by the traditional fee-for-service program.

Worth remembering: MA is no longer a side program. For most beneficiaries, Medicare Advantage is Medicare. That means MA’s payment rules, its risk adjustment, its prior authorization practices, and its quality measures are now the dominant operating environment for anyone caring for older adults, which is why this course exists.

What Medicare Advantage is

MA, sometimes called Part C, lets private plans contract with CMS to deliver Medicare benefits. The essential structure:

• Plans receive a capitated payment from CMS for each enrollee, risk-adjusted for how sick that person is. This is the population-based payment from the intro course, operating at national scale.
• Plans must cover everything traditional Medicare covers, and typically add benefits traditional Medicare does not, such as dental, vision, hearing, and reduced cost sharing.
• Plans manage care through networks and utilization management, tools traditional Medicare largely does not use.

Why this is a value-based care course

Medicare Advantage is the largest risk-bearing arrangement in American healthcare. Every mechanism this curriculum has covered appears here at scale: capitation, risk adjustment, quality measurement tied to payment, utilization management, and the delegation of risk further downstream to provider groups.

It is also the most contested. MA’s payment accuracy, its coding practices, its prior authorization, and its measured value are all subjects of active policy fights, litigation, and disputed evidence. This course takes them one at a time and reports what the sources actually show.

Key takeaways

• Roughly 55 percent of eligible Medicare beneficiaries, just over 35 million people, are in Medicare Advantage as of 2026.
• MA plans receive risk-adjusted capitation, must cover everything traditional Medicare covers, and typically add supplemental benefits.
• MA is the largest risk-bearing arrangement in US healthcare, and the most actively contested.

Sources

• KFF, Medicare Advantage in 2026: Enrollment Update and Key Trends (opens in a new tab)
• MedPAC, The Medicare Advantage Program: Status Report (March 2026) (opens in a new tab)