State tax levels indicate both the tax burden and the services a state can afford to provide residents.

In addition to federal income tax collected by the United States, most individual U.S. states collect a state income tax. Some local governments also impose an income tax, often based on state income tax calculations. Forty-two states and many localities in the United States impose an income tax on individuals. Eight states impose no state income tax, and a ninth, New Hampshire, imposes an individual income tax on dividends and interest income but not other forms of income. Forty-seven states and many localities impose a tax on the income of corporations.