Colorado State Income Tax: Rates and Who Pays in 2023-2024

Colorado’s income tax rate is 4.4%. It is one of 11 states with a flat income tax.

Colorado state income tax returns are due April 15, 2024. People who need more time to file can take advantage of the state’s automatic six-month tax extension but should remember to pay at least 90% of their tax bill to avoid incurring penalties and interest^[0]

Colorado state income tax rates and tax brackets

For tax year 2023 (taxes filed in 2024), Colorado’s state income tax rate is 4.4%. Previously, Colorado taxed income at a fixed rate of 4.55%, but the passage of Proposition 121 lowered the rate by 0.15% for tax years 2022 and forward^[0]

Colorado’s flat-tax approach is different from how the federal government and several other states collect taxes. Instead of taxing chunks of a taxpayer’s income at progressively higher rates depending on how much they make, the state levies a flat 4.4% on taxable income.

» MORE: See what federal tax bracket you’re in

What is Colorado’s standard deduction?

Unlike some other states, Colorado does not have a state standard deduction. This is because a taxpayer’s federal taxable income — which already takes into account the application of the federal standard deduction or the taxpayer's itemized deductions — is generally used as a basis for calculating taxes owed to Colorado^[0]

Single and joint filers who make over a certain amount of income, however, may also be asked to add back in a portion of their federal itemized deductions when figuring their Colorado taxable income. See the Individual Income Tax Guide on the Colorado Department of Revenue’s website for more information^[0]

» MORE: Learn about the federal standard deduction and when to take it

Do I have to pay Colorado state income tax?

Colorado residents and part-year residents who file a federal tax return typically also need to file a Colorado state income tax return. Nonresidents who earn Colorado-sourced income may also have a filing obligation.

» MORE: How much do I need to make to file a federal income tax return?

Am I a resident for Colorado income tax purposes?

There are three types of residency statuses when it comes to Colorado state tax. They determine what portion of your income the state will tax.

• Resident.

• Part-year resident.

• Nonresident.

Resident status rules

Colorado generally considers you a resident for tax purposes if:

• You have a permanent home in Colorado to which you return after traveling from the state. This home could be a rental, condo, house or mobile home; or

• You maintain a permanent home in Colorado and spend more than six months (182 days) of the year in the state.

Students who attend college in a state outside Colorado, do not intend to establish residency in that state post-graduation or are supported by parents who live in Colorado while in school are considered residents of Colorado by the state taxing authority — regardless of whether they voted or applied for a driver’s license or ID in the state where they attend college.

Special rules may apply to military personnel or service members and to those who file jointly with someone who is a resident of Colorado, even if they themselves are not. The Colorado Department of Revenue’s website has the details.

Residents of Colorado file Form DR 0104.

Part-year resident status rules

If you lived in Colorado when the year started but then moved to another state, you may be considered a part-year resident for Colorado tax purposes. Likewise, if you lived in another state when the calendar year started but then moved to Colorado and took steps to establish residency, you’re also probably considered a part-year resident.

Colorado part-year residents file Form DR 0104 and corresponding schedule DR 0104PN.

Nonresident status rules

Colorado defines nonresidents as people who do not live in Colorado but may have briefly worked in Colorado or made income from Colorado-based sources.

If you’re a nonresident with taxable Colorado income, you may have a state filing obligation if you also must file a federal return. Nonresidents file Form DR 0104 and schedule DR 0104PN to help calculate Colorado tax liability.

» Need help? How to find a tax preparer near you

Colorado tax credits

Colorado child tax credit (COCTC)

Colorado taxpayers with dependent children who were below the age of 6 in 2023 (i.e., born in 2018 or later) may be able to claim a refundable state-level child tax credit on their 2024 state tax returns. The credit is worth up to 10% to 60% of the federal child tax credit amount. Taxpayers who made above $75,000 ($85,000 for joint filers) do not qualify^[0]

Colorado earned income tax credit (COEITC)

The earned income tax credit is a refundable tax break for low-to-moderate income earners. Qualified Colorado filers can claim Colorado's state-level version that is modeled after the federal benefit. For the 2023 tax year, the COEITC is worth up to 50% of an eligible filer's federal earned income tax credit^[0]

Colorado inheritance and estate tax

Colorado does not impose an inheritance tax or estate tax on the state level^[0]

Colorado sales tax

Colorado’s statewide sales tax is 2.9%. This tax applies to items such as the sale of prepared food and drinks, goods or merchandise, and hotel rentals or other accommodations. It doesn’t apply to things such as groceries or medications, which are tax-exempt.

Counties and cities can also levy a local sales tax on top of the state one, bringing the total sales tax up to 11.2% in some areas^[0]

4 things to know about Colorado income tax