The 17 highest-union-density states have all adopted the Affordable Care Act’s Medicaid expansion: Number of high-, medium-, and low-union-density states that had adopted the Medicaid expansion as of 2026
| Expanded Medicaid | Did not expand Medicaid | |
|---|---|---|
| Low | 10 | 7 |
| Medium | 14 | 3 |
| High | 17 | 0 |
Notes: Union density is defined as the share of workers in the state who are members of a union based on the variable “unmem” from EPI extracts of CPS-ORG microdata.
Notes: Union density is defined as the share of workers in the state who are members of a union based on the variable “union” from EPI extracts of CPS-ORG microdata. Low-union-density states are the 17 states with the lowest average union densities from 2023–2025 (with union densities ranging from 2.5% to 6.1%). Medium-union-density states are the 17 states (including D.C.) in the middle of the union-density rankings (with union densities ranging from 6.8% to 11.6%). High-union-density states are the 17 states with the highest average union densities from 2023–2025 (greater than 11.9%).
Sources: EPI analysis of 2023–2025 Current Population Survey Outgoing Rotation Group (CPS-ORG) microdata for all workers ages 16 and older; KFF, “Status of State Medicaid Expansion Decisions,” May 21, 2026.