Income tax in the United States income taxes. This foreign tax credit is limited to that part of current year tax caused by foreign source income. Determining such part involves determining the source of income and allocating and apportioning deductions to that income. States tax resident individuals and corporations on their worldwide income, but few allow a credit for foreign taxes. In addition, Federal income tax may be imposed on non-resident non-citizens, including corporations, on U.S. source income. Federal tax applies to interest, dividends, royalties, and certain other income of nonresident aliens and foreign corporations at a flat rate of 30%. This rate is often reduced
State income tax particularly with respect to partnerships. Most states require taxpayers to make quarterly payments of tax not expected to be satisfied by withholding tax. All states impose penalties for failing to file required tax returns and/or pay tax when due. In addition, all states impose interest charges on late payments of tax, and generally also on additional taxes due upon adjustment by the taxing authority. Forty-three states impose a tax on the income of individuals, sometimes referred to as personal income tax. State income tax rates vary widely from state to state. The states imposing an income tax on individuals tax