Most states levy an income tax on their residents that is in addition to the federal income tax. Laws vary from state to state but in most states the state income tax is a tax on the annual earnings of individuals, corporations, trusts, limited liability companies, and other legal entities.
There are nine states that do not have a state income tax—including Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, and Wyoming. But New Hampshire levies a tax on capital gains and Washington state recently enacted a tax on extraordinary profits from the sale of financial assets over $250,000.
New Hampshire is one of the nine states in the United States that does not levy a traditional state income tax on earned income. This means that for most residents, there is no tax on wages, salaries, and other forms of compensation that are typically subject to income tax in other states. However, New Hampshire does impose a tax on interest and dividends income, which is a form of tax on investment income. As of the knowledge cutoff in 2023, New Hampshire does not tax capital gains directly, but the state does tax interest and dividends at a 5% rate for individuals with more than $2,400 of such income annually ($4,800 for joint filers). It's important to note that while there is no broad-based income tax, New Hampshire does have other forms of state taxation, including property taxes and business taxes.