When will the U.S. enact legislation expanding ACA marketplace premium tax credits?

My median prediction for legislation expanding ACA marketplace premium tax credits is 26th December 2030, driven by the strong opening created if Democrats secure unified government in 2029–30.

The enhanced ACA premium tax credits applied during 2021–2025, including eligibility above 400% of the federal poverty level. This forecast measures enactment of a subsequent statutory expansion, including partial restoration, rather than passage by a single chamber or an administrative announcement. IRS background: https://www.irs.gov/credits-deductions/premium-tax-credit-ptc-overview

Resolves on the enactment date of the first federal law after 23 October 2026 that expands premium tax credits under Internal Revenue Code section 36B for marketplace coverage in 2027 or a later year by either lowering the statutory household-income contribution percentages used to calculate the credit, relative to the schedule otherwise applicable for that year, or extending eligibility to households above 400% of the federal poverty level.

The expansion must apply generally to otherwise eligible marketplace households within the affected income bands, rather than solely to a named occupation, employer, or locality. Partial restoration of the 2021–2025 enhancements qualifies. Ordinary inflation indexing, extension of unchanged baseline credits, an executive announcement, or a separate payment outside section 36B does not qualify.

The enactment date counts even if the coverage change begins later. Enactment by presidential signature, without signature, or by a successful veto override qualifies. Resolve from the enacted public law, cross-checked against IRS implementation guidance.