Maine currently conforms to the Internal Revenue Code in effect as of December 31, 2024. As a result, none of the numerous federal tax changes enacted in the One Big Beautiful Bill Act (OBBBA) have been incorporated in Maine tax law.
However, a law enacted last legislative session gives Governor Mills the authority to make temporary changes to Maine tax administration when there is a lag between federal tax changes and Maine legislative conformity, or nonconformity, to such changes. (P.L. 2025, c. 336, effective September 24, 2025.)
The new law requires any temporary changes to be consistent with legislative intent as reflected in enacted Maine income tax laws, and to consider the budgetary implications of the changes and the extent to which the changes reduce complexity for both taxpayers and Maine Revenue Services (MRS).
On September 30, 2025, Kirsten Figueroa, Commissioner of the Department of Administrative and Financial Services (DAFS), issued a report to Governor Mills, outlining certain federal tax law changes made by the One Big Beautiful Bill Act and making conformity recommendations for the 2025 tax year. The report stresses that MRS should receive the governor’s guidance by early October in order to draft new tax forms without delaying the upcoming filing season.
On October 1, 2025, Governor Mills issued a Determination and Direction to the State Tax Assessor, which adopted the DAFS conformity recommendations in full.
The governor’s determination instructs MRS to conform to the OBBBA’s increased IRC § 179 expensing limits and to the immediate deduction of research and development expenses for certain small businesses only and retroactive to the 2022-2024 tax years only.
On the other hand, the governor’s determination instructs MRS to decouple in 2025 from significant OBBBA tax relief including:
The Maine Legislature is scheduled to return for the Second Regular Session of the 132nd Legislature in January 2026.
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