Revenue and taxation; income tax; rate; effective date.

HB 1209 modifies Oklahoma's individual income tax rates, lowering the top marginal rate for most filers starting in 2024. It reduces the highest tax bracket from 5.50% to 4.75% for single filers and from 5.50% to 4.75% for married couples filing jointly, effective for tax years beginning in 2024. The bill also eliminates the deduction for federal income taxes paid when calculating taxable income. These changes apply to all Oklahoma residents and nonresidents filing individual income tax returns. The bill specifies a further adjustment for tax years beginning in 2026, though the exact rates are not detailed in the provided text.