State Tax Day - Current, S.5, Colorado—Multiple Taxes: Adjustment Required for Calculation and Refunding of Excess State Revenues Under TABOR, (Jun 10, 2026)

Colorado has enacted legislation directing the State Controller to correct the accounting of state fiscal year 2024-25 spending to accurately reflect the revenue reductions caused by the One Big Beautiful Bill Act (OBBBA) (P.L. 119-21), and to make corresponding changes to taxpayer refunds under the Colorado Taxpayers’ Bill of Rights (TABOR). OBBBA was signed into law four days after the end of fiscal year 2024-25, which meant that there was a mismatch between actual state revenues and those recorded for TABOR refund purposes.

If in September 2026 the Controller certifies that state revenues for fiscal year 2025-26 did not exceed the constitutional spending limit, the Controller must, before November 16, 2026, determine the amount of the fiscal year 2024-25 surplus that was over-refunded due to the timing of OBBBA. The over-refund amount for fiscal year 2024-25 is the difference between:

• the originally certified refund amount for fiscal year 2024-25; and

• the amount that would have been required to be refunded for fiscal year 2024-25 taking into account the reduction in state revenues caused by OBBBA.

The over-refund amount will be used to adjust TABOR refunds for fiscal years commencing on or after July 1, 2026. However, no more than half of this over-refund can offset future TABOR refunds for any fiscal year.

H.B. 1419, Laws 2026, effective June 3, 2026