How would expiration of ACA premium tax credits affect 2026/2027 Marketplace premiums and enrollment numbers?

1. What the federal scorekeepers say: modest gross premium increases, but big coverage effects

The Congressional Budget Office’s baseline finds that expiration would lift average gross benchmark premiums by 4.3% in 2026 and by 7.7% in 2027, with a 7.9% average increase over 2026–2034—CBO ties part of that jump to healthier enrollees leaving the Marketplaces when subsidies shrink ^[1]. CBO’s estimate refers to gross premiums (what insurers charge) rather than the net premiums consumers pay after tax credits ^[1].

2. Why consumer-facing premium pain looks far larger than the CBO’s gross‑premium numbers

Analysts emphasize that net, out‑of‑pocket premium payments for subsidized enrollees respond to subsidy rules—KFF’s modeling shows average consumer premium payments would rise 114% in 2026 (from $888 to $1,904), driven by the rollback of enhanced caps and 2026 rate proposals by insurers ^{[2] [3]}. KFF and other trackers also document insurers’ own rate filings that assume the subsidy lapse and add several percentage points to 2026 rate requests (median proposed rate increase ~18%), amplifying consumer cost exposure ^{[6] [7] [8]}.

3. Enrollment effects: models disagree on magnitude but agree directionally

Projections vary. CBO’s modeling implies a persistent, multi‑year reduction in subsidized enrollment and projects an average annual increase in the uninsured of about 3.8 million without extension ^[1]. Urban Institute–derived and some advocacy analyses produce larger one‑year shocks—estimates cited include roughly 4.8 million becoming uninsured in 2026 or even as high as about 5–7 million people losing Marketplace coverage depending on assumptions and the timing of employer‑market shifts ^{[4] [5]}. The common finding: a large net drop in Marketplace enrollment and a substantial rise in uninsurance if credits lapse ^{[1] [4] [5]}.

4. What insurers’ rate filings are already signaling for 2026–2027

Insurer filings in several states and DC show firms explicitly attributing part of their 2026 rate increases to the expected end of enhanced credits—those filings add roughly 4 percentage points on average to rates in the samples examined, with some carriers reporting 6–7% of their total increase tied to subsidy expiration ^{[9] [6]}. Across 312 insurers nationally, Peterson‑KFF found a median proposed increase of 18% for 2026, with some carriers specifying morbidity or selection impacts that would apply if subsidies end ^[8].

5. Who would be hit hardest — and why geography and age matter

KFF and mapping analyses show the burden is uneven: middle‑income households above 400% FPL would lose eligibility and face the steepest relative increases, and older enrollees and people in higher‑premium areas would see the largest absolute dollar increases ^{[10] [7]}. Low‑income people currently shielded by generous subsidies would also see big jumps in required contributions if enhancements lapse ^{[7] [2]}.

6. Interaction with other enrollment policy changes raises uncertainty for 2027

Other regulatory and procedural shifts (shortened open‑enrollment windows, proposed Marketplace integrity rules, changes to auto‑renewal and special enrollment policies) could further depress enrollment and accelerate churn into less comprehensive coverage—analysts warn these parallel changes complicate any simple 2026→2027 projection and could amplify coverage losses into 2027 ^{[11] [12] [13]}.

7. Limitations, disagreements and the policy choice ahead

Estimates diverge because models use different assumptions about consumer responsiveness, insurer pricing behavior, and spillovers to employer coverage; CBO focuses on long‑run averages for gross premiums while KFF and Urban Institute emphasize consumer net costs and short‑term enrollment responses ^{[1] [2] [4] [5]}. Available sources do not mention how state policy responses (e.g., targeted state subsidies) would fully offset the national numbers; state actions are noted but not quantified in these pieces ^{[9] [8]}.

8. Bottom line for 2026–2027: expect higher premiums for consumers, fewer enrollees, and sharp variation by model and place

All reputable analyses agree lapse of enhanced credits would raise gross premiums modestly (CBO ~4–8%) but produce much larger increases in the premiums consumers pay (KFF ~114% on average) and substantial enrollment losses (CBO ~3.8 million uninsured rise; other studies up to ~4.8–7+ million coverage losses), with local impacts differing by age, income, and market ^{[1] [2] [3] [4] [5]}. Policymakers’ decisions about extending or modifying credits will determine whether these projected shocks materialize ^{[1] [14]}.