Exemptions directly reduce your taxable income. You are allowed a personal exemption for yourself, your spouse if married filing jointly, and each person you can claim as a dependent. For 2008, the exemption amount is $3,500, unless your income exceeds certain limits (see Phaseout of Exemptions).

You can take a personal exemption for yourself unless another taxpayer can claim you as a dependent. Even if the other taxpayer does not take an exemption for you, you cannot claim the personal exemption. 

If you file a joint return, you can claim an exemption for your spouse.

If you are filing separate returns, or as head of household, you can claim an exemption for your spouse only if you meet all of the following:

• Your spouse has no gross income.
• Your spouse is not filing a return.
• Your spouse was not another taxpayer's dependent.

If your spouse could be claimed as someone else's dependent, you cannot claim the exemption, even if the other taxpayer does not claim the exemption for your spouse.

If your spouse died during the year and you did not remarry, you can claim an exemption for your spouse if you are filing a joint return in the year of your spouse's death. 

You can claim one exemption for each person you can claim as a dependent. Even if your dependent files a return, you can still claim a personal exemption for him or her.

You can take one exemption for each qualifying child or relative if the person meets three tests:

• Dependent Taxpayer Test
  • If you could be claimed as a dependent by another taxpayer, you cannot claim anyone else as your dependent. This is true even if you have a qualifying child or relative.

• Joint Return Test
  • You generally cannot claim a married person as a dependent if he or she files a joint return.
  • This test does not apply if a joint return is filed by a dependent only to claim a refund and no tax liability exists for either spouse, even if they filed separate returns.

• Citizen or Resident Test
  • You cannot claim an exemption for a dependent unless the person is a U.S. citizen, resident alien, national, or a resident of Canada or Mexico for at least part of the year.
  • If you are a U.S. citizen or national who has legally adopted a child who is not a U.S. citizen, resident alien, or national, this test is met if the dependent lived as a member of your household the entire tax year.

If you are a non-resident alien, generally you can only claim an exemption for yourself. You cannot claim an exemption for your spouse or any dependents.

This does not apply to residents of Canada, Mexico, or certain residents of India and Korea. This also does not apply if you are a non-resident alien married to a U.S. citizen or resident alien, and have chosen to be treated as a resident of the United States. 

For 2008, the exemption amount is gradually reduced, but not below $2,333 per exemption, as your modified adjusted gross income exceeds these amounts:

• $119,975 for married filing separately filing status
• $159,950 for single filing status
• $199,950 for head of household filing status
• $239,950 for married filing jointly or qualifying widow(er) filing status

For more information, see IRS Publication 501.