This bill amends Sections 217 and 2385.13 of Title 68 of the Oklahoma Statutes, which pertain to tax interest rates. The amendments modify the interest rate applied to delinquent taxes and underpayments of estimated tax payments. Specifically, the bill replaces the previous interest rate of one and one-quarter percent (1.25%) per month with a new annual rate calculated using Wall Street Prime as of January 1 of that year, plus three percentage points. This change applies to both delinquent taxes and deficiencies assessed by the Oklahoma Tax Commission. Additionally, the interest rate for underpayments of estimated tax payments is also updated to reflect the same calculation method.

The bill also includes provisions for penalties related to delinquent taxes, stating that a ten percent penalty will be added to the total amount due if taxes are not paid within specified timeframes. Furthermore, it establishes that the new interest rates will apply to all delinquencies occurring on or after the effective date of the act, which is set for November 1, 2025. The bill aims to clarify the application of these interest rate changes and ensure consistency in the treatment of tax delinquencies and underpayments.