Medicare Monthly Enrollment by State & County 2013-2026 (CMS)

Explore the official Medicare Monthly Enrollment dataset from the Centers for Medicare & Medicaid Services (CMS). This filter-ready sheet contains 587,117 rows of Medicare enrollment counts for every year and month from 2013 through July 2026, reported at the national, state, and county level.

What is in the dataset?

Each row is a geography-and-period record with 60 fields of beneficiary counts: total Medicare beneficiaries, Original Medicare versus Medicare Advantage and other plans, Part A and Part B coverage, Part D prescription drug enrollment split by stand-alone PDP and MA-PD plans, Low-Income Subsidy status, dual Medicare-Medicaid eligibility categories (QMB, SLMB, QDWI/QI, full and partial dual), and demographics by age band, sex, race and ethnicity, disability, and ESRD status. State abbreviations, county names, and FIPS codes make it easy to join with other public health, provider, and plan datasets.

Common use cases

• Measure Medicare Advantage penetration and Original Medicare share by county, state, or month.
• Track Medicare enrollment growth and demographic shifts from 2013 to 2026.
• Size Part D, dual-eligible, and Low-Income Subsidy populations for market planning.
• Build enrollment denominators for provider, claims, pricing, and plan-landscape analysis.
• Create county-level maps and territory prioritization for healthcare sales and policy research.

Counts are aggregate CMS administrative enrollment statistics, not individual beneficiary records; small-cell values suppressed by CMS are left blank. The source is a U.S. government work and is in the public domain.