If you qualify to file as head of household, your tax rate usually will be lower than the rates for single or married filing separately. You will also receive a higher standard deduction than if you file as single or married filing separately.
The standard deduction amount for head of household on 2008 tax year is $8000.
There are rules for claiming the head of house hold status.
Per the IRS publication 501:
You may be able to file as head of household if you meet all the following requirements.
You are unmarried or "considered unmarried" on the last day of the year.
You paid more than half the cost of keeping up a home for the year.
A "qualifying person" lived with you in the home for more than half the year (except for temporary absences, such as school). However, if the "qualifying person" is your dependent parent, he or she does not have to live with you.
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