Data Notice: Figures, rates, and statistics cited in this article are based on the most recent available data at time of writing and may reflect projections or prior-year figures. Always verify current numbers with official sources before making financial, medical, or educational decisions.

Income Tax in Colorado: Complete Guide 2026

Tax information is for educational purposes only and does not constitute tax advice. Consult a licensed tax professional for your specific situation.

Colorado uses a flat income tax rate, making it one of the simpler state tax systems in the country. The state’s Taxpayer Bill of Rights (TABOR) limits how quickly revenue can grow, leading to periodic taxpayer refunds when collections exceed caps. Understanding Colorado’s flat rate, TABOR refunds, and available deductions helps residents plan effectively.

This guide covers Colorado’s 2026 income tax rate, how the system works, key subtractions and credits, and tips for optimizing your filing.

Colorado 2026 Income Tax Rate

Colorado levies a single flat rate on all taxable income:

Tax Rate	Taxable Income Range
~4.4%	All taxable income

Key figures:

Flat tax rate: ~4.4%
Colorado taxable income starts with federal taxable income
No state-level standard deduction (uses federal standard deduction through conformity)
TABOR refund: Amount varies annually based on state revenue collections
Filing threshold: Must file if required to file a federal return

Colorado’s rate has decreased in recent years through voter-approved reductions. The state previously used a ~4.55% rate, which was reduced to ~4.4% effective for the 2024 tax year and beyond.

How Colorado Income Tax Works

Federal Conformity

Colorado is a strong federal conformity state. Your Colorado taxable income starts with your federal taxable income (line 15 of Form 1040). This means you automatically benefit from the federal standard deduction or itemized deductions without needing to recalculate them for state purposes.

Calculating Your Tax

Start with your federal taxable income
Add Colorado additions (state/local bond interest from other states, etc.)
Subtract Colorado subtractions (state income tax refund, pension/annuity exclusions, etc.)
Multiply the result by ~4.4%
Subtract applicable credits
Your result is your Colorado income tax due

TABOR Refunds

Colorado’s Taxpayer Bill of Rights caps the amount of revenue the state can retain. When actual revenue exceeds the cap, the excess is refunded to taxpayers. TABOR refunds are distributed through various mechanisms, including sales tax refunds, property tax credits, and direct payments. For the 2026 tax year, the estimated TABOR refund is approximately ~$800 per individual filer, though actual amounts depend on revenue collections and legislative decisions.

Retirement Income

Colorado offers a retirement income subtraction for taxpayers age ~55 to ~64 of up to ~$20,000 and for those age ~65 and older of up to ~$24,000. This subtraction applies to all types of qualifying retirement income, including pensions, 401(k) distributions, IRA withdrawals, and Social Security benefits.

Social Security benefits included in federal taxable income can also be subtracted on the Colorado return for qualifying taxpayers, subject to the overall retirement subtraction limit.

Colorado vs. Neighboring States

State	Top Rate	System	Social Security Taxed?
Colorado	~4.4%	Flat	Partially (with subtraction)
Utah	~4.65%	Flat	Yes (with credit)
Wyoming	~0%	None	No
Nebraska	~5.84%	Graduated	Partially
New Mexico	~5.9%	Graduated	No
Kansas	~5.7%	Graduated	No

Colorado’s flat ~4.4% rate is competitive among its neighbors. Only Wyoming, with no income tax, is lower. Utah’s flat rate is slightly higher, and Nebraska, New Mexico, and Kansas all have higher top rates with graduated systems.

See the full comparison in our state income tax rates comparison.

Key Subtractions and Credits

Colorado offers several subtractions from federal taxable income and tax credits:

Retirement income subtraction: Up to ~$20,000 (ages ~55-~64) or ~$24,000 (age ~65+)
Colorado EITC: ~25% of the federal Earned Income Tax Credit (refundable)
Child tax credit: Colorado offers a state child tax credit for qualifying families
Child care contribution credit: ~50% of contributions to qualifying child care facilities
Enterprise zone credits: Credits for businesses and investments in designated enterprise zones
Renewable energy credits: Credits for solar and other renewable energy installations
Charitable contribution subtraction: Additional subtraction of ~5% of charitable contributions for taxpayers who claim the federal standard deduction
TABOR refund: Direct refund or credit when state revenue exceeds caps

Tips for Managing Your Colorado Income Tax

Track your TABOR refund. TABOR refunds are issued automatically but through different mechanisms. Some are applied as credits on your state return while others are sent as direct payments. Ensure you receive and properly report your refund.
Maximize retirement subtractions. If you are ~55 or older, claim the full retirement income subtraction. This can eliminate state tax on up to ~$24,000 of retirement income for those ~65 and older.
Use the Colorado EITC. At ~25% of the federal credit, Colorado’s state EITC is one of the more generous in the country. If you qualify for the federal EITC, claim the state credit as well. It is refundable, meaning it can result in a payment to you.
Charitable giving with standard deduction. Colorado uniquely offers an additional subtraction for charitable contributions even if you take the federal standard deduction. If you make charitable gifts, claim this ~5% subtraction on your Colorado return.
Plan estimated payments for non-wage income. Colorado requires estimated payments if you expect to owe more than ~$1,000 after credits. Self-employed taxpayers and investors should make quarterly payments. Review our self-employment tax guide for strategies.
Understand local taxes. Some Colorado cities, including Denver, Aurora, and Glendale, levy their own local income or occupational privilege taxes. These are separate from the state tax and may require separate filings.
Review federal conformity changes. Because Colorado starts with federal taxable income, any changes to federal tax law automatically affect your Colorado return. Stay informed about federal changes through our federal income tax guide.

Key Takeaways

Colorado uses a flat income tax rate of ~4.4% for 2026, applied to federal taxable income with state-specific adjustments.
TABOR limits state revenue growth and results in periodic refunds to taxpayers, estimated at approximately ~$800 per filer for 2026.
Generous retirement income subtractions of up to ~$24,000 benefit taxpayers age ~65 and older.
Colorado’s refundable state EITC at ~25% of the federal credit provides meaningful relief for lower-income workers.
The state offers a unique charitable contribution subtraction even for taxpayers who take the federal standard deduction.
Some Colorado cities levy additional local income taxes that require separate attention.

Next Steps

Federal Income Tax Guide 2026 — Understand how federal conformity affects your Colorado return.
State Income Tax Rates Comparison 2026 — Compare Colorado’s flat rate with other state systems.
Tax Bracket Calculator — Calculate your combined federal and Colorado tax liability.
Find a CPA Near You — Connect with a Colorado tax professional for personalized advice.