Personal exemption (United States)

Under United States tax law, a personal exemption is an amount that a resident taxpayer is entitled to claim as a tax deduction against personal income in calculating taxable income and consequently federal income tax. It has the effect of reducing income tax payable, even to tax-free level, but not so as to result in a tax refund. In 2015 the personal exemption amount was US $4,000. The exemption for 2016 is $4,050, though the actual tax benefit depends on the taxpayer's marginal tax rate. The personal exemption amount is adjusted each year for inflation.

The exemption is composed of personal exemptions for the individual taxpayer and, as appropriate, his or her family and dependents, as provided in Internal Revenue Code at 26 U.S.C. § 151. The income tax liability is calculated by applying the appropriate tax rate to the taxable income (26 U.S.C. § 1).

Section 151 of the Internal Revenue Code was enacted in August 1954, and enabled a certain level of income, “personal exemptions”, not to be subject to federal income tax. The exemption was intended to insulate from taxation roughly at the minimal amount of money someone would need to get by at a subsistence level (i.e., enough money for food, clothes, shelter, etc.). The amount listed in §151 (see below), even adjusted for inflation, may seem inadequate for a taxpayer to subsist on. In addition to personal exemptions, taxpayers may claim other deductions that further reduce the level of income subject to taxation.

Generally speaking, a personal exemption can be claimed by the taxpayer, §151(b), and their qualifying dependents, §151(c). A personal exemption may also be claimed for a spouse if (1) the couple files separately, (2) the spouse has no gross income, and (3) the spouse is not the dependent of another, §151(b). For taxpayers filing a joint return with their spouse, the IRS Regulations allow two personal exemptions as well, §1.151-1(b).

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