Your filing status on your federal tax return is a category that identifies you based on your marital and family situation, according to the IRS. It is an important factor in determining whether you must file a return, the amount of your standard deduction and your correct amount of tax. If more than one filing status applies to you, you may choose the one that gives you the lowest tax obligation.

There are five possible filing statuses: Single, Married Filing Jointly, Married Filing Separately, Head of Household and Qualifying Widow(er) with Dependent Child. Your marital status on the last day of the year determines your status for the entire year.

Generally, if you are unmarried, divorced or legally separated according to your state law, your filing status is Single.

If you are married, you and your spouse may file either a joint return or separate returns. If your spouse died during the year and you have not remarried, you may still file a joint return with that spouse for the year of death.

Generally, to qualify for Head of Household status, you must be unmarried and have provided more than half the cost of keeping up a home that was the main home for yourself and a qualifying relative for more than half the year. You may also qualify if you are married but did not live with your spouse at any time during the last six months of the tax year and you provided more than half the cost of keeping up a home for you and your dependent child for more than half the year.

If your spouse died during 2002 or 2003, you may be able to file as a Qualifying Widow or Widower. To do this you must meet all four of the following tests:

1. You were entitled to file a joint return with your spouse in the year of death,
2. You did not remarry before the end of 2004,
3. You have a child, stepchild, adopted child or foster child who qualifies as your dependent for the year, and
4. You paid more than half the cost of keeping up your home, which was the main home of that child, for the whole year.

You can find more detailed information on each filing status in Publication 501, Exemptions, Standard Deduction, and Filing Information. You can download forms and publications or order them by calling toll free 1-800-TAX-FORM (1-800-829-3676).