On March 22, 2024, the Centers for Consumer Information and Insurance Oversight (CCIIO) at the Centers for Medicare and Medicaid Services (CMS) released more detailed information on the nearly 21.5 million people — a historic high by far — who enrolled in the Affordable Care Act’s marketplaces during the 2024 Open Enrollment Period.

According to the new data, marketplace enrollment among children under age 18 increased by about 611,000 between the 2023 and 2024 Open Enrollment Periods.  That is an increase of about 39.5 percent.  And since 2020, marketplace child enrollment has more than doubled, rising by more than 1.1 million.  Children as a share of total marketplace enrollment, however, has not increased, remaining between 9 percent and 10 percent for the 2020-2024 period, with the 2024 child share of 10.1 percent actually less than the 10.6 percent in 2020.  (See graph.)

This substantial increase in marketplace enrollment among children is very welcome, as it will help reduce the number and share of children who are uninsured in families with incomes too high for Medicaid and the Children’s Health Insurance Program (CHIP).  But the 611,000 increase in child marketplace enrollment between 2023 and 2024 offsets only a modest share of the total net Medicaid enrollment losses among children since unwinding of the continuous coverage requirement began last year.  Our latest data indicate that child Medicaid enrollment has declined by 4.61 million during unwinding.  Moreover, many of the children losing Medicaid coverage likely remain eligible, as they were disenrolled for procedural reasons and are therefore ineligible for subsidies to purchase marketplace plans.  In addition, there were other key factors besides unwinding that likely drove up child marketplace enrollment.  This includes the continued impact of the enhanced marketplace subsidies included in the 2021 American Rescue Plan Act, which were extended by the Inflation Reduction Act through 2025, and the elimination of the “family glitch” starting in 2023.

That being said, further growth in marketplace enrollment, not just during the fall 2025 Open Enrollment Period but also during Special Enrollment Periods (related to loss of Medicaid and CHIP and having incomes below 150 percent of the federal poverty line, among others) over the course of the year could lead to Medicaid re-enrollment among some eligible children.  As their parents obtain marketplace coverage, some of their children will be identified as Medicaid-eligible because child Medicaid income eligibility levels are significantly higher than for parents and the children will be then transferred back to state Medicaid programs.  But as I have written in my blog series about marketplace transitions among those losing Medicaid coverage, state Medicaid programs also need to do much more to increase child Medicaid enrollment and offset the dire enrollment losses since unwinding commenced.  That includes significantly reducing procedural termination rates during unwinding and beyond, taking up actionable strategies to promote continuous coverage and working on robust outreach and enrollment efforts to target eligible children so they can be re-enrolled as quickly as possible to reduce gaps in coverage.