Illinois vs Colorado: State Income Tax Compared
Side-by-side comparison of state income tax between Illinois and Colorado, plus combined federal + state take-home pay.
| Metric | IL Illinois | CO Colorado |
|---|---|---|
| State tax type | Flat | Flat |
| Top state rate | 4.95% | 4.4% |
| Standard deduction | $13,900 | $13,900 |
Estimated at $75,000 income (federal + state)
Illinois net income ≈ $62,054 (17.3% effective rate)
Colorado net income ≈ $62,390 (16.8% effective rate)
Illinois Pros & Cons
- ✓Simple flat 4.95% rate — same rate at every income level
- ✓$13,900 standard deduction before state tax applies
- ✕Top earners face a state marginal rate of up to 4.95%
- ✕Higher top state rate than Colorado by 0.5 points
Colorado Pros & Cons
- ✓Lower top state tax rate than Illinois (4.4% vs 4.95%)
- ✓Simple flat 4.4% rate — same rate at every income level
- ✓$13,900 standard deduction before state tax applies
- ✕Top earners face a state marginal rate of up to 4.4%
Frequently asked questions
At $75,000 income, how does take-home pay compare?+
On an estimated $75,000 income (federal + state combined), our calculator shows Illinois take-home of roughly $62,054 (17.3% effective rate) versus Colorado's $62,390 (16.8% effective rate). Use the calculator above with your own income for a personalized estimate.
Which has the higher state tax rate, Illinois or Colorado?+
Illinois has the higher top state marginal rate at 4.95%, compared to Colorado's 4.4%.
Does Illinois or Colorado have no income tax?+
No — both Illinois and Colorado levy a state income tax.
Are these figures exact?+
No — these are estimates generated from a simplified model of federal and state tax brackets, intended for planning purposes. They don't account for every credit, allowance, local tax, or surcharge. Always confirm current-year figures with the IRS and each state's tax authority before filing.
Figures shown are estimates and do not include every deduction, credit, local tax, or surcharge that may apply. Always confirm with the IRS and each state's official tax authority.