OK HB1539

Reduces Oklahoma individual income tax rates by 0.25 percentage points across all brackets for tax years beginning January 1, 2024, lowering the top marginal rate from 4.75% to 4.50%

Establishes automatic future rate reductions of 0.25 percentage points when the State Board of Equalization certifies at its December meeting that total state revenue collections exceeded the base year amount by at least $300 million

Sets fiscal year ending June 30, 2023 as the initial base year for revenue comparisons, with the base year amount adjusted upward after each rate reduction is triggered

Requires the State Board of Equalization to begin making annual revenue determinations at its December 2025 meeting and continue until all individual income tax rates reach zero

Takes effect November 1, 2025