Colorado Tax Calculator
Colorado's constitution requires a single flat rate applied to all taxable income, so there are no brackets to navigate. The state starts from your federal taxable income and layers on its own additions and subtractions, and it offers age-based exemptions that reduce or eliminate state tax on Social Security for older residents. Enter your income above to see your Colorado state tax calculated instantly.
State Tax
$4,400Effective Rate
4.40%Marginal Rate
4.40%| Rate | Bracket Range | Tax |
|---|---|---|
| 4.40% | $0+ | $4,400 |
| Total | $4,400 | |
How Colorado income tax works
- Colorado multiplies your Colorado taxable income by one constitutionally mandated flat rate.
- The state starts from federal taxable income, then applies Colorado-specific additions and subtractions.
- Older residents may qualify for an exemption that reduces or removes state tax on Social Security income.
Need the exact bracket thresholds instead of an estimate? See the Colorado tax brackets for 2026 .
Estimate your Colorado property tax by county, compare every state at the state tax brackets hub , or see the full tax-by-state directory .
Frequently asked questions
How is Colorado income tax calculated?
Colorado applies a single flat rate to your Colorado taxable income, which starts from your federal taxable income with state-specific adjustments. The calculator applies that rate directly to your entered income.
Does Colorado tax Social Security benefits?
Colorado offers an exemption that fully removes Social Security from state tax for older residents, with a partial exemption available to somewhat younger retirees.
Why does Colorado use a flat rate?
The Colorado Constitution requires a single flat income tax rate rather than tiered brackets, so every taxpayer pays the same percentage of their Colorado taxable income.
How much state tax will I pay in Colorado?
Since Colorado uses a flat rate, your state tax is that rate applied to your Colorado taxable income. Enter your figures above for an instant total.
Sources
Related insights
Use these guides for rule explanations, planning context, and follow-up questions beyond the calculator result.
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