Mco Market Share By State Data: Dataset Structure and Field Coverage

It measures how much of a state's Medicaid membership and Medicaid dollars move through comprehensive risk-based managed care organizations instead of fee-for-service, and it is published in three interchangeable framings: enrollment share, spending share, and penetration rates cut by eligibility group or plan type. KFF — State Health Policy: Medicaid & CHIP Indicators carries all three inside its Managed Care Market Tracker — 11 managed-care-specific indicators sitting in a catalog of roughly 209 state-level Medicaid & CHIP indicators. Coverage runs to all 50 states plus DC and territories where available, always with a United States aggregate row, and individual indicators return up to 21 year-periods of state rows of about 50 records each.

Definitions decide whether two states are even comparable. KFF tracks MCO enrollment apart from broader counts of enrolleees in any managed care arrangement, pins current-period figures to July 1 reporting dates, and breaks some series out by eligibility group, plan type, parent firm or month. Fix one framing before ranking states, and start from the Medicaid managed care definition so numerator and denominator match the source.

Three layers do the work, and they stack rather than compete. The analysis layer is KFF — State Health Policy: Medicaid & CHIP Indicators: its 11 Market Tracker indicators are the only ready-made state-level share series in this slice, spanning MCO enrollment, spending, penetration rates, parent-firm financials and medical-loss-ratio requirements. The benchmark layer is KFF — 10 Things to Know About Medicaid Managed Care (2026), which turns the July 1, 2024 enrollment snapshot and FY 2024 spending into state choropleth maps you can eyeball before building anything. The raw layer is Data.Medicaid.gov — CMS Medicaid Data Portal: 549 public-domain datasets as of August 2026, 25 of them managed-care-titled, refreshed monthly.

You can reproduce any published share figure from public-domain numerators in about five steps:

Share of enrollment is only half the competitive question; the other half is which parent firms hold it. KFF's Market Tracker answers with dedicated parent-firm financials indicators and medical-loss-ratio requirements by state, both cut at state level and some by parent firm. The KFF — 10 Things to Know About Medicaid Managed Care (2026) brief frames the structural side: market concentration, capitation rate-setting, and state directed payments, with contracting status current to July 2025.

Grain differs across those two monitoring surfaces in ways that matter to a share model. The topic hub indexes publications — titles, dates and types across 274 listing pages — so it tells you when a state's program design changed but hands you no numbers. The full-text search returns catalog records whose underlying data ranges from national summaries down to state-program-plan-year rows, so a newly harvested filing can drop straight into your panel. Pair them deliberately: the hub as the alert, the search as the delivery mechanism.

Continue along the managed-health-care trail: