Changes in Coverage by State and in Selected Metropolitan Areas

A woman and her daughter speak after filling out forms in a doctor's office waiting room.

The Affordable Care Act (ACA) reduced the percentage of uninsured adults in all 50 states in its first year of full implementation.


The Issue

Based on American Community Survey (ACS) data, the national uninsured rate fell by 3.6 percentage points between 2013 and 2014, mostly due to the ACA.

Key Findings

Since the first year of ACA implementation:

  • Between 2013 and 2014, the percentage of people in the United States without health insurance fell from 16.9 percent to 13.4 percent.

  • Non-Medicaid expansion states reduced their uninsured rate by 2.8 percentage points compared to 4.2 percentage points in Medicaid expansion states.

  • Reductions in the uninsured rate were broad, touching every demographic and socioeconomic group.


The implementation of the ACA led to a drop in the number of uninsured that was far larger than would be expected based on economic and demographic trends. States that experienced the largest drops were those that expanded Medicaid eligibility under the ACA; however, large coverage gaps remain in states that have not expanded Medicaid.

About the Urban Institute

The nonprofit Urban Institute is dedicated to elevating the debate on social and economic policy. For nearly five decades, Urban scholars have conducted research and offered evidence-based solutions that improve lives and strengthen communities across a rapidly urbanizing world. Their objective research helps expand opportunities for all, reduce hardship among the most vulnerable, and strengthen the effectiveness of the public sector. Visit the Urban Institute’s Health Policy Center for more information specific to its staff and its recent research.