The vast majority of net-new ACA Exchange enrollments since enhanced subsidies took effect have been among consumers eligible for zero-premium plans, according to a Department of Health and Human Services report published June 26, 2026. The finding sharpens the stakes around a fiscal cliff that is now just months away: the enhanced premium tax credits are set to expire at the end of 2025 — a deadline that will push out-of-pocket costs up sharply for millions of current enrollees.

Total Exchange enrollment for 2026 reached 23.1 million, with consumers selecting or being automatically re-enrolled through HealthCare.gov during an Open Enrollment Period that ran through January 15, 2026. That figure is near the program's all-time high, sustained in part by a subsidy structure that has effectively brought premium costs to zero for a large segment of the eligible population.

Who Gained — and What They Stand to Lose

The concentration of enrollment growth among zero-premium-eligible consumers is a structural fact with direct policy consequences. When enhanced credits lapse, these enrollees will face the steepest relative cost increase: moving from a $0 monthly premium to a meaningful dollar figure is a different behavioral shock than a marginal rate adjustment for someone already paying several hundred dollars a month. Churn in this cohort — largely lower-income enrollees who qualified under the expanded subsidy thresholds — tends to be fast and disproportionate relative to premium movement.

The ASPE analysis from January 2025 quantified the coverage gains attributable to enhanced subsidies over the 2021–2024 period, providing the baseline against which any post-expiration drop would be measured. That analysis predates the 2026 enrollment cycle, but the ASPE's June 2026 enrollment report carries the story forward: aggregate enrollment held near record levels through the most recently completed open enrollment, even as expiration loomed.

The Trump Administration's Alternative

President Trump has outlined a plan to restructure federal health insurance support by replacing government subsidies with direct payments to consumers, according to Reuters. Details on the mechanism, income thresholds, and payment amounts have not been fully specified in public-facing documents, and it is not yet clear whether a legislative vehicle exists to move the proposal before the subsidy cliff hits.

That timing gap matters operationally. Insurers set Exchange premiums on an annual cycle, and carriers need regulatory and actuarial certainty well before open enrollment begins in the fall to price plans accurately. If a replacement framework is not enacted and implemented before the relevant rate-setting deadlines — typically late summer — carriers will price 2026 and beyond using the post-enhanced-subsidy baseline, which means higher premiums appear in the market regardless of downstream congressional action.

What the Enrollment Composition Means for Future Counts

The zero-premium enrollment concentration also matters for how analysts interpret headline enrollment numbers. A figure like 23.1 million looks durable until you disaggregate it. If the cohort most sensitive to premium changes — those currently at zero cost-sharing — exits at high rates after expiration, the total could contract sharply even if higher-income enrollees remain relatively stable. That asymmetry is what makes the ASPE composition finding analytically significant: it reframes the headline number as more fragile than its absolute size suggests.

Policy staff tracking this issue will be watching for two indicators in quick succession: first, whether Congress acts on subsidy extension or a replacement scheme before the year ends; second, how carriers respond in their preliminary rate filings for the next plan year. Those filings will function as an early market signal of what insurers expect enrollment to look like without enhanced credits — or with whatever replacement policy is on the table.

For now, the record shows a program that grew substantially under a specific subsidy regime, with most of that growth concentrated in the population most exposed to expiration.