Millions of people who buy health insurance through HealthCare.gov or a state marketplace could owe back every dollar of excess subsidy if their income ends up higher than they estimated. The Treasury Department and the IRS issued proposed regulations on Oct. 14 that would write that change into federal tax rules, and the proposal was published in the Federal Register the next day.
The key detail is easy to miss. Congress ended the repayment cap in the July 2025 tax and spending law, and the change applies to tax years starting after Dec. 31, 2025. The new regulations are still only proposed, but they show how the IRS intends to apply the change when people reconcile their 2026 coverage on returns filed in 2027.
