State Income Tax Comparison Calculator
State income tax rates vary dramatically across the United States, from 0% in nine no-tax states to over 13% in California for the highest earners. This calculator lets you compare the estimated state income tax you would pay in two different states on the same taxable income. Since state tax structures differ (flat rates vs. graduated brackets), this tool uses an effective rate approach: enter your taxable income and the applicable effective state rate for each state to compare annual state tax, monthly impact, and the annual difference. State rate inputs are user-editable so you can enter exact figures from your state revenue agency.
State tax comparison formula
State 1 tax = taxable income * (state 1 rate / 100)
State 2 tax = taxable income * (state 2 rate / 100)
Annual difference = |State 1 tax - State 2 tax|
Monthly difference = annual difference / 12
This uses an effective rate approach. For states with graduated brackets, you can find your effective rate by dividing your total state tax by your taxable income, or by consulting your state's tax agency. State tax rates and bracket thresholds change annually.
2025 state income tax overview
- No income tax states (2025): Alaska, Florida, Nevada, New Hampshire (wages), South Dakota, Tennessee (wages), Texas, Washington, Wyoming.
- Flat rate states include Colorado (4.40%), Illinois (4.95%), Michigan (4.25%), and Pennsylvania (3.07%).
- California has the highest top marginal rate at 13.3% on income above $1 million; it uses graduated brackets starting at 1%.
- Some states allow additional deductions or exemptions not captured by a simple effective rate comparison.
- Local income taxes (city or county) can add another 1-4% in cities like New York, Philadelphia, and Detroit.
State income tax comparison: frequently asked questions
Which states have no income tax?
Nine states impose no state income tax on wages: Alaska, Florida, Nevada, New Hampshire (on earned wages; interest and dividends were phased out by 2025), South Dakota, Tennessee (wages only), Texas, Washington, and Wyoming. Moving to one of these states can produce significant tax savings for high earners.
How are state income tax rates structured?
States use three main structures: flat rates (one rate on all income, e.g., Illinois at 4.95%), graduated brackets (like the federal system, e.g., California with 1%-13.3% brackets), and no income tax. Some states also exempt a portion of income via standard deductions or exemptions.
Is state income tax deductible on federal taxes?
State income taxes are deductible if you itemize federal deductions, but only as part of the SALT (state and local tax) deduction, which is capped at $10,000 per federal return. Most taxpayers who pay significant state income tax will hit this cap.
Do cities and counties also impose income taxes?
Yes. Many cities and some counties impose local income taxes. Examples include New York City, Philadelphia, Baltimore, Columbus, and Detroit. Local taxes are not included in this state-level comparison calculator.
Does state income tax affect my federal tax deduction?
Yes, if you itemize. State income taxes paid are included in the SALT deduction (capped at $10,000). If you pay more state tax in a high-rate state and itemize, you recoup some of the difference on your federal return, but only up to the $10,000 cap.
Official sources
- Federation of Tax Administrators: State Tax Agency Directory.
- IRS: IRS 2025 Tax Adjustments (federal context).
Reviewed by the CalculatorHub team, edited by James Graham, 15 June 2026. See our methodology.