Income tax in the United States to file tax returns for federal and many state and local returns. Tax as determined by the taxpayer may be adjusted by the taxing jurisdiction. A tax is imposed on net taxable income in the United States by the federal, most state, and some local governments. Income tax is imposed on individuals, corporations, estates, and trusts. The definition of net taxable income for most sub-federal jurisdictions mostly follows the federal definition. The rate of tax at the federal level is graduated; that is, the tax rates on higher amounts of income are higher than on lower amounts. Some states and
Income tax in the United States insurance (Social Security) taxes in 2016. The table below also does not reflect changes, effective with 2013 law, which increased the average tax paid by the top 1% to the highest levels since 1979, at an effective rate of 33%, while most other taxpayers have remained near the lowest levels since 1979. Income tax is imposed as a tax rate times taxable income. Taxable income is defined as gross income less allowable deductions. Taxable income as determined for federal tax purposes may be modified for state tax purposes. The Internal Revenue Code states that "gross income means all income from