With UnitedHealthcare and Humana controlling the largest shares, operators should assess their exposure to these specific payers and prioritize proactive contracting strategies to secure favorable terms.
Most Medicare Advantage Markets are Dominated by One or Two Insurers
Enrollment in Medicare Advantage, the private plan alternative to traditional Medicare, has increased steadily since 2010. The average beneficiary has access to 34 Medicare Advantage plans with prescription drug coverage in 2025, double the number available in 2018. However, recent analysis finds that Medicare Advantage markets are highly concentrated, suggesting that the growth in enrollment and plan availability has not occurred in the context of a competitive market. Virtually all Medicare Advantage insurance markets were highly concentrated (79%) or very highly concentrated (18%) in 2024. Nine in ten (90%) Medicare beneficiaries lived in counties where more than half of all Medicare Advantage enrollees were in plans sponsored by one or two firms in 2024.
— KFF, July 14, 2025
Zhu, Nicole et al. “Most Medicare Advantage Markets are Dominated by One or Two Insurers.” KFF, 14 Jul. 2025. https://www.kff.org/medicare/most-medicare-advantage-markets-are-dominated-by-one-or-two-insurers/.
✔ Comply with every payer's rules
✔ Equip your team with the Playbook
✔ Monitor rates and payer trends
