Income tax in the United States

The federal government of the United States imposes a progressive tax on the taxable income of individuals, corporations, trusts, decedents' estates, and certain bankruptcy estates. Some state and municipal governments also impose income taxes. The first Federal income tax was imposed (under Article I, section 8, clause 1 of the U.S. Constitution) during the Civil War, then again in the 1890s, and again after the Sixteenth Amendment was ratified in 1913. Current income taxes are imposed under these constitutional provisions and various sections of Subtitle A of the Internal Revenue Code of 1986, as amended, including (imposing income tax on the taxable income of individuals, estates and trusts) and (imposing income tax on the taxable income of corporations).
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