Colorado Income Tax Guide 2026: Rates, Brackets & Calculator

Colorado has a flat 4.4% statutory income tax that applies equally to all income levels — making it one of the simpler state tax systems in the country.

Colorado Tax Rate 2026

Unlike states with progressive brackets, Colorado taxes everyone at the same statutory rate. Whether you earn $30,000 or $300,000, you pay 4.4% on Colorado taxable income — though Colorado’s TABOR mechanism has in some years produced a temporary effective rate reduction when state revenue exceeds constitutional limits; confirm whether that applies for the current tax year.

How Much Will I Pay in Colorado Tax?

Colorado Tax Calculation

Colorado starts with your federal taxable income (after the federal standard deduction), then allows certain additions and subtractions. The result is multiplied by 4.4%.

Colorado Additions to Income

• State income tax refund (if previously deducted)
• Certain out-of-state municipal bond interest
• Lump-sum distributions not using 10-year averaging

Colorado Subtractions from Income

• Social Security benefits taxed federally
• Military retirement pay (confirm current exclusion amounts by age, as Colorado has adjusted these in recent years)
• Colorado pension/annuity exclusion (for ages 55+; confirm current amount)
• Qualified state tuition program (529) contributions (confirm current per-beneficiary limit)
• ABLE account contributions

Colorado vs. Other States

Colorado’s flat rate is competitive compared to neighboring states.

Colorado Standard Deduction

Colorado doesn’t have its own standard deduction. Your federal taxable income serves as the starting point, which means you’ve already taken the federal standard deduction:

Colorado Tax Credits

Colorado Family Affordability Tax Credit

Colorado has offered a Family Affordability Tax Credit (FATC) for lower-income families in recent years. Confirm current per-child amounts and income limits with the Colorado Department of Revenue, as this credit’s parameters have changed year to year.

Colorado TABOR Refund

Under TABOR (Taxpayer’s Bill of Rights), when state revenue exceeds constitutional limits, Colorado issues refunds to taxpayers. Confirm the current refund amount, as it varies significantly year to year based on state revenue and is not a fixed number.

Who Must File a Colorado Tax Return?

You must file if:

• You’re a Colorado resident with taxable income
• You’re a nonresident with Colorado-source income
• You’re eligible for a refund (even with no tax liability)
• You want to claim the EITC or Family Affordability Tax Credit

Filing Threshold

Because Colorado uses federal taxable income as the starting point, the effective threshold generally matches federal filing requirements. However, you should file to claim refundable credits even if you have no tax liability.

Colorado Local Taxes

Several Colorado cities levy additional flat occupational privilege taxes (a fixed dollar amount per pay period, not a percentage) on employers and employees, including Denver, Aurora, and Greenwood Village. Confirm current rates with each city, as these are typically withheld by employers for employees working in those cities.

Colorado Sales Tax

Colorado has one of the lower state sales tax rates, but local taxes can push combined rates well above the state rate in some areas.

Colorado Property Tax

Confirm the current average effective property tax rate, median home value, and median property tax bill with a source like the Tax Foundation, as these figures change over time and were not independently re-verified this session. Colorado’s property taxes have historically been below the national average, partially offset by higher home values.

How to File Colorado Taxes

Filing deadline: April 15 (same as federal)

Extension: Automatic 6-month extension if you file a federal extension

Colorado Tax Tips

1. Maximize 529 Contributions

Colorado allows a per-beneficiary deduction for 529 plan contributions — confirm the current limit, as this is one of the more generous state benefits and has been adjusted over time.

2. Check for TABOR Refunds

Don’t miss claiming your refund when eligible. Check your filing status and income level each year, since the refund amount and mechanism can change.

3. Claim the EITC

Colorado matches a percentage of the federal EITC — confirm the current percentage, which can add meaningfully to your refund.

4. Military Benefits

Colorado offers deductions for military retirement pay — confirm current age-based exclusion amounts.

5. Senior Benefits

At age 55+, Colorado begins allowing pension exclusions that increase with age — confirm current amounts.

Colorado Part-Year and Nonresident Rules

Part-year residents calculate tax on total income, then prorate based on CO income percentage.

Key Takeaways

1. Colorado’s flat 4.4% statutory rate makes tax calculation simple
2. Federal taxable income is the starting point — no separate state standard deduction
3. 529 contributions can be deducted up to a per-beneficiary limit — confirm current amount
4. TABOR refunds may provide additional cash back when state revenue exceeds constitutional limits
5. Colorado EITC adds a percentage of the federal credit for eligible filers
6. Filing deadline is April 15 — same as federal

For a side-by-side comparison of every state’s income tax rates, see state income tax rates by state 2026 and best and worst states for taxes 2026. Federal income tax applies on top of state taxes — see 2026 federal income tax brackets to calculate your combined liability.

Written by WealthVieu

WealthVieu researches and writes data-driven personal finance guides using primary sources including the IRS, Bureau of Labor Statistics, Federal Reserve, and Census Bureau.