Colorado State Income Tax: What You Need to Know
Colorado levies a state income tax on its residents. The state uses flat rate: 4.25% with a top marginal rate of 4.25%. This state tax is in addition to the federal income tax, which has seven brackets ranging from 10% to 37% for the 2026 tax year.
Colorado uses a flat income tax rate applied to federal taxable income with minor adjustments.
To calculate your total income tax burden in Colorado, you need to consider both federal and state taxes. Your federal tax is calculated on your taxable income after the standard deduction ($15,000 for single filers, $30,000 for married filing jointly in 2026). Your Colorado state tax is then calculated separately based on Colorado's own brackets and rules.
How Colorado Income Tax Compares
Colorado's top rate of 4.25% is near the national average for states that levy an income tax. For context, the highest state income tax rate in the nation is California's 13.3%, while the lowest non-zero flat rate is Pennsylvania's 3.07%.
9 states currently have no broad-based state income tax: Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, Wyoming. If you're comparing tax burdens across states, remember to also consider sales tax, property tax, and the overall cost of living.
Federal Income Tax Brackets for 2026
Regardless of which state you live in, all U.S. residents are subject to federal income tax. The 2026 federal tax brackets for single filers are:
- 10% — Income up to $11,600
- 12% — $11,601 to $47,150
- 22% — $47,151 to $100,525
- 24% — $100,526 to $191,950
- 32% — $191,951 to $243,725
- 35% — $243,726 to $609,350
- 37% — Over $609,350
The standard deduction for 2026 is $15,000 for single filers and $30,000 for married filing jointly. Use our federal income tax calculator to see exactly how much you owe and how your income is taxed across each bracket.
Tips to Reduce Your Colorado Tax Bill
- Maximize retirement contributions — 401(k) and IRA contributions reduce your taxable income for both federal and most state returns.
- Use tax-advantaged accounts — HSAs and FSAs lower your taxable income while covering healthcare and dependent care costs.
- Claim all deductions — Review Colorado's specific deductions and credits, which may differ from federal rules.
- Consider filing status — Married Filing Jointly often results in lower taxes thanks to wider brackets and a larger standard deduction.
Frequently Asked Questions
Does Colorado have a state income tax?
Yes, Colorado has a state income tax with flat rate: 4.25% and a top rate of 4.25%.
How do I calculate my total income tax in Colorado?
Calculate your federal income tax using our calculator, then add your Colorado state tax based on Colorado's brackets and rates. The combined amount is your total income tax obligation.