Colorado charges a flat 4.4% state income tax on most wages and retirement income

Colorado's state income tax is 4.4% of your federal taxable income. This rate applies to wages, salaries, retirement distributions, and most other income sources. Unlike many states, Colorado does not use tax brackets — everyone pays the same percentage regardless of how much they earn.

The 4.4% rate has been in place since 2000. It applies to your federal taxable income, which means you calculate it after taking the standard deduction or itemizing deductions on your federal return. Colorado does not allow a separate state deduction.

If you work in Colorado but live in another state, or live in Colorado but work in another state, you may owe taxes to both states. The state where you earned the income generally has the first claim, though you can usually claim a credit on your home state return for taxes paid elsewhere.

Key Takeaways

  • Colorado's state income tax rate is a flat 4.4% applied to your federal taxable income, with no tax brackets.
  • You calculate Colorado tax after taking your federal deductions, not before.
  • Retirement income, including distributions from IRAs and 401(k)s, is taxed at the same 4.4% rate.
  • If you work across state lines, you may owe income tax to both Colorado and your other state, though you can claim a credit to avoid double taxation.
  • Social Security benefits are not taxed by Colorado, even if they are taxed federally.

What income is subject to Colorado tax

Colorado taxes wages, salaries, bonuses, commissions, and tips. It also taxes interest, dividends, capital gains, and rental income. Retirement distributions from IRAs, 401(k)s, and pensions are taxed the same way as wages — at the flat 4.4% rate.

Self-employment income is taxed by Colorado after you subtract business expenses and the self-employment tax deduction. You report this on your federal return first, then explore the 4.4% rate to your federal taxable income.

Social Security benefits are not taxed by Colorado, even if you have to include them in your federal taxable income. This is one of the few income sources that escapes the 4.4% rate entirely.

How Colorado tax is withheld from your paycheck

Your employer withholds Colorado income tax from each paycheck based on the W-4 form you complete. The withholding is calculated as 4.4% of your federal taxable wages after federal withholding and deductions.

If you have multiple jobs, work part of the year, or have significant non-wage income, your withholding may not match what you actually owe. You can adjust your withholding by submitting a new W-4 to your employer, or you can wait and settle the difference when you file your return.

If you are self-employed or have income with no withholding, you may need to make estimated tax payments to Colorado four times per year. The due dates are April 15, June 15, September 15, and January 15 of the following year.

Filing a Colorado state income tax return

You file Colorado taxes using Form 104, the Colorado Individual Income Tax Return. You must file if your income exceeds the threshold set by Colorado — this threshold changes yearly and depends on your filing status and age. For 2024, the threshold is roughly $14,600 for single filers under 65, though you should check the current year's instructions.

You can file online through the Colorado Department of Revenue website, by mail, or through a tax software provider. The important date is the same as the federal important date, usually April 15.

If you file your federal return electronically, you can also file your Colorado return electronically at no cost. Many tax software providers include Colorado filing as part of their service.

Deductions and credits available in Colorado

Colorado allows a standard deduction that matches the federal standard deduction. You cannot claim a separate Colorado deduction — you use the same deduction amount you used on your federal return.

Colorado offers a few tax credits that may reduce what you owe. The earned income tax credit (EITC) is available to low-income workers and is calculated based on your federal EITC. Colorado also offers a property tax exemption for seniors and disabled persons, though this is a property tax benefit, not an income tax credit.

If you paid taxes to another state, you can claim a credit for those taxes on your Colorado return, though the credit is limited to the amount of Colorado tax you owe.

Tax rates for different types of income

Colorado does not differentiate tax rates by income type — all income is taxed at 4.4%. Long-term capital gains are not taxed at a lower rate in Colorado, even though they may receive preferential treatment federally. Short-term capital gains and long-term capital gains are both subject to the same 4.4% state rate.

may have access to dividends are also taxed at 4.4% in Colorado, not at a preferential rate. This is one area where Colorado's tax code is simpler than the federal code but potentially more expensive for investors.

Retirement income, including distributions from traditional IRAs, Roth conversions, and pension payments, is all taxed at 4.4%. Colorado does not offer a retirement income exemption like some states do.

Special situations: part-year residents and nonresidents

If you moved to or from Colorado during the year, you file as a part-year resident. You report only the income you earned while a Colorado resident and pay tax on that portion. You will need to show the date you moved and documentation of your residency change.

If you worked in Colorado but did not live there, you owe Colorado tax on the income you earned in the state. You also file a return in your home state, which may tax the same income. You can claim a credit in your home state for taxes paid to Colorado to reduce double taxation.

Military members stationed in Colorado are generally treated as nonresidents for tax purposes and do not owe Colorado tax on military pay, though they may owe tax on other income earned in the state.

Frequently Asked Questions

Do I have to pay Colorado income tax if I just moved there?

You owe Colorado tax only on income earned after you become a resident. If you moved mid-year, you file as a part-year resident and report only the income earned after your move date. You will need to show proof of when you established residency, such as a lease, utility bill, or driver's license.

Is Colorado income tax deductible on my federal return?

Yes, if you itemize deductions on your federal return, you can deduct state and local income taxes (SALT) up to $10,000 per year. If you take the standard deduction, you cannot deduct Colorado income tax separately. Most taxpayers benefit more from the standard deduction.

What happens if I underpay my Colorado taxes?

If you owe more than $500 when you file, you may owe a penalty and interest on the unpaid amount. The penalty is typically 5% of the unpaid tax, plus interest calculated daily. You can avoid penalties by paying estimated taxes if you have income with no withholding.

Does Colorado tax retirement income differently?

No. Distributions from IRAs, 401(k)s, and pensions are all taxed at the same 4.4% rate as wages. Colorado does not offer a retirement income exemption. Social Security is the only major retirement income source that escapes Colorado tax.

Can I claim a credit for taxes paid to another state?

Yes, you can claim a credit on your Colorado return for income taxes paid to another state, but the credit cannot exceed the Colorado tax you owe. This prevents you from getting a refund for out-of-state taxes, but it does prevent double taxation.