- Colorado voters decide November 3, 2026, whether to cap the rate at 4.4% for individuals and corporations.
- Proposition 136 would make the current rate a legal ceiling starting January 1, 2027, not cut taxes.
- A competing graduated-tax proposal could conflict with the cap; the measure receiving more votes would likely prevail.
Colorado voters will decide November 3, 2026, whether to place a legal ceiling on the state income-tax rate. Proposition 136 would cap the rate for individuals and corporations at 4.4%, starting January 1, 2027.
The measure would not lower the current rate. It would make that rate the maximum allowed under state law.
Free toolSubstantial Presence Test Calculator
Advance Colorado backs the proposal. As of October 3, 2026, it remains a pending ballot measure, not enacted law.
A separate measure proposes a graduated tax structure. The two proposals could conflict if both win voter approval.
The proposal would freeze the ceiling, not cut the current rate
A yes vote would add a statutory cap calculated against federal taxable income. A no vote would leave the current rate in place without adding that limit.
The measure would become state law and needs a simple majority to pass. It would apply to both individual and corporate income taxes.
The choice, then, is between keeping the current rate without a statutory ceiling and putting that ceiling into law. It does not itself change the rate or raise state revenue.
Amendment 87 would set higher rates above $500,000
Amendment 87 would create six income brackets. Its proposed rates rise for income above $500,000.
| Amendment 87 income range | Proposed rate |
|---|---|
| Up to $25,000 | 3.7% |
| $25,001 to $100,000 | 4.2% |
| $100,001 to $500,000 | 4.4% |
| $500,001 to $750,000 | 7.4% |
| $750,001 to $1 million | 7.9% |
| Above $1 million | 8.4% |
If both measures pass, the competing rules could be incompatible. The conflict would likely be resolved in favor of whichever measure receives more votes.
Supporters cite predictability while critics point to existing limits
Advance Colorado presents the cap as a way to prevent future increases above the current rate. The Colorado Chamber of Commerce also supports the measure, saying it would provide “a predictable and competitive tax structure for businesses and individuals.”
Kristi Burton Brown, executive vice president of Advance Colorado, argued that the state does not need additional tax revenue.
“I do not think that you have to raise more taxes”
Critics say the proposed ceiling adds little because Colorado already requires voter approval for tax increases. That restriction comes from TABOR, the Taxpayer’s Bill of Rights voters adopted in 1992.
Colorado voters approved the current flat income-tax rate in 2022. The proposal would not change the rate or state revenue on its own, but could affect the outcome if voters also approve the graduated-tax measure.
Polis has condemned the competing tax plan
The two proposals reflect a dispute over whether Colorado should retain a flat income tax or move to higher rates for some high earners. Amendment 87 would establish that graduated structure; the cap proposal would put a maximum rate into state statute.
Jared Polis, Colorado’s Democratic governor, criticized Amendment 87, calling it “bad policy that would destroy our economy.”
Voters will decide both measures on November 3, 2026.
