The proposed bill introduces the "Surplus Funds Tax Credit Act" as a new chapter in Title 44 of the General Laws concerning taxation. It mandates that if net state tax revenues in any fiscal year exceed the projected revenue estimates contained in the budget for that fiscal year, the excess amount will result in a credit equal to the total amount of such excess. This credit will be applied to the current personal income tax liability of all taxpayers on a proportional basis relative to their personal income tax liabilities incurred in the immediately preceding taxable year.

The state budget officer is responsible for determining whether the net state tax revenue exceeds the projected revenue estimates and reporting the excess amount to the director of the department of revenue by September 1 of each fiscal year. The final determination and calculations for refunds to taxpayers must be completed by September 20 of each fiscal year.

The bill also allows for enforcement of its provisions by taxpayers through the state courts, provided that a petition is filed by at least 28 taxable inhabitants, with no more than seven from any one county. Successful petitioners are entitled to recover reasonable attorneys' fees and other costs incurred in maintaining such a suit. The director of the department of revenue is granted the authority to promulgate rules and regulations necessary to implement the provisions of this chapter. The act is set to take effect on July 1, 2026.