A personal exemption acts like a tax deduction on a tax form and individuals can claim one for themselves and any dependents they support in order to reduce taxable income and lower taxes according to About.com. For 2015, the personal exemption amount is $4,000, an increase of $50 over 2014.
Individuals may take one exemption for themselves as long as they are not able to be claimed as a dependent by another taxpayer, even if that taxpayer does not actually claim them as a dependent, according to the IRS. On a joint tax return, married individuals may also take an exemption for their spouse. If filing separate tax returns, a personal exemption for a spouse can only be taken if the spouse had no gross income, is not filing a return and is not the dependent of another taxpayer. One personal exemption may be taken for each additional dependent that a taxpayer can claim, even if the dependent files a tax return.