Colorado Income Tax Calculator 2026
Calculate your Colorado state income tax with our free 2026 calculator. Colorado has a flat 4.40% income tax rate, making it one of the simplest state tax systems in the U.S.
Calculate Your Colorado State Tax
Understanding Colorado Income Tax
Colorado uses a flat income tax rate of 4.40% as of 2026. This means all Colorado residents pay the same percentage of their taxable income regardless of how much they earn. This is simpler than progressive tax systems used by many other states.
Key Features:
- Flat rate: 4.40% applies to all income levels
- Federal standard deduction: Colorado uses the federal standard deduction amounts ($14,050 single, $28,100 married for 2026)
- No Social Security tax: Social Security benefits are fully exempt from Colorado state income tax
- TABOR refunds: Colorado's Taxpayer's Bill of Rights (TABOR) may result in refunds when state revenue exceeds limits
- Federal tax not deductible: Unlike some states, you cannot deduct federal income tax on your Colorado return
Colorado Tax Deductions and Credits
Standard Deduction (2026)
| Filing Status | Standard Deduction |
|---|---|
| Single | $14,050 |
| Married Filing Jointly | $28,100 |
| Married Filing Separately | $14,050 |
| Head of Household | $21,000 |
Common Colorado Tax Credits
- Child Care Contribution Credit: Credit for contributions to qualifying child care facilities (up to 50% of contribution, max $100,000)
- Innovative Motor Vehicle Credit: Credit for electric and alternative fuel vehicles
- Conservation Easement Tax Credit: Credit for conservation easement donations
- Historic Property Preservation Credit: 20-25% of qualified expenses for historic property rehabilitation
- Enterprise Zone Credits: Various credits for businesses and individuals in economically distressed areas
- Rural and Frontier Healthcare Preceptor Credit: Credit for medical professionals training students in rural areas
How to Reduce Your Colorado Tax Bill
- Maximize retirement contributions: Traditional IRA and 401(k) contributions reduce your federal AGI, which flows through to Colorado
- Health Savings Accounts (HSAs): Contributions are deductible and reduce your Colorado taxable income
- Claim all available credits: Colorado offers numerous credits for childcare, renewable energy, and more
- Business expense deductions: If self-employed, ensure you're claiming all legitimate business expenses
- Property tax/rent rebate: Seniors and disabled veterans may qualify for property tax/rent rebates
- 529 college savings plan: Colorado taxpayers can deduct up to $20,000 per beneficiary ($30,000 married) for CollegeInvest contributions
How Colorado Tax Compares to Other States
| State | Income Tax Rate | Type |
|---|---|---|
| Colorado | 4.40% | Flat |
| California | 1% – 13.3% | Progressive |
| Texas | 0% | No income tax |
| Florida | 0% | No income tax |
| Utah | 4.65% | Flat |
| Wyoming | 0% | No income tax |
| Illinois | 4.95% | Flat |
| New York | 4% – 10.9% | Progressive |
Colorado's 4.40% flat rate is lower than most states with income tax and significantly simpler to calculate than progressive systems. However, it's higher than neighboring states with no income tax (Texas, Wyoming, Nevada).
Frequently Asked Questions
What is the Colorado state income tax rate?
Colorado has a flat income tax rate of 4.40% as of 2026. Unlike many states with progressive tax brackets, all Colorado residents pay the same percentage regardless of income level.
What is the standard deduction for Colorado state tax?
For 2026, Colorado's standard deduction is $14,050 for single filers and $28,100 for married filing jointly. Colorado does not have its own standard deduction; it uses the federal standard deduction amounts.
Does Colorado tax Social Security income?
As of 2022, Colorado no longer taxes Social Security benefits for residents. Full exemption applies to all Social Security retirement and disability benefits, making Colorado more tax-friendly for retirees.
Can I deduct federal income tax on my Colorado return?
No. Colorado does not allow you to deduct federal income tax paid from your state taxable income. However, you can claim various Colorado-specific credits and deductions that may reduce your state tax liability.
When are Colorado state taxes due?
Colorado state income tax returns are due on the same date as federal returns — typically April 15th each year. Extensions are available but you must still pay any estimated tax owed by the original deadline to avoid penalties.
Do I have to pay estimated quarterly taxes in Colorado?
Yes. If you expect to owe more than $1,000 in Colorado state income tax for the year, you must make quarterly estimated tax payments. Due dates are typically April 15, June 15, September 15, and January 15.
What is a TABOR refund?
TABOR (Taxpayer's Bill of Rights) is a Colorado constitutional amendment that limits state revenue. When the state collects more revenue than allowed, it must refund the excess to taxpayers. TABOR refunds have been issued in several recent years.
Does Colorado tax retirement income?
Colorado provides a pension/annuity subtraction for taxpayers age 55-64 (up to $20,000) and 65+ (up to $24,000). Social Security is fully exempt. Other retirement income like 401(k) and IRA distributions may qualify for partial subtraction.