The Earned Income Tax Credit (EIC) is a refundable tax credit that reduces or eliminates the tax paid by low-income workers.

Changes for 2009

The American Recovery and Reinvestment Act (ARRA) increased Earned Income Tax Credit amounts and expanded the credit for workers with three or more qualifying children. These changes are set to expire after the 2009 and 2010 tax years.
A new rule has been adopted for situations where both a parent and another relative can qualify to claim a child. The person who is not the parent can only claim the child when his or her AGI is higher than any parent of the child.
Some additional requirements have been added to the definition of a qualifying child (see below).

Amount of Credit

Tax Year 2009 maximum credit:

Requirements to Claim Credit

An Individual Taxpayer Identification Number (ITIN) is not sufficient.

Your SSN card must not have "Not valid for employment" on it.

Your filing status must be single, head of household, qualifying widow(er), or married filing jointly.
You must be a U.S. citizen living in the U.S. more than half the year, or a resident alien for the entire year.
You cannot have foreign earned income.
Your investment income must be less than $3,100.
Your adjusted gross income must be less than:

$43,279 ($48,279 if married filing jointly) if you have three or more qualifying children

$40,295 ($45,295 if married filing jointly) if you have two or more qualifying children

$35,463 ($40,463 if married filing jointly) if you have one qualifying child

$13,440 ($18,440 if married filing jointly) if you do not have any qualifying children

Additional Requirements if You Have a Qualifying Child

The child must have a valid Social Security Number (SSN).
The child must be younger than you, unless the child is disabled (new for 2009).
The child must not have filed a joint return except to claim a refund (new for 2009).
The child's relationship to you must be any of the following:

Son or daughter

Stepchild

Eligible foster child

Sibling, half-sibling, or step-sibling

A descendant of any of the above, e.g, your grandchild

Under 19 at the end of the current tax year

Under 24 at the end of the current tax year and a student

Permanently and totally disabled at anytime during the year, regardless of age

The child must have lived with you in the United States for more than half of the current tax year. A child is considered to have lived with you if the child was born or died in the current tax year and lived with you the entire time he or she was alive. Temporary absences, including school, vacation, medical care, military service, or detention in a juvenile facility, count as time lived with you.
The child cannot be used by anyone else to claim EIC.
It is possible that one child might be claimed by two or more persons in one calendar year. In this event, the child will be the qualifying child of the parents first, and then the taxpayer with the highest adjusted gross income (AGI). If both of the child's parents claim the credit, the parent with whom the child resides the longest may claim the credit. If the child resides with both parents an equal amount of time, the parent with the highest AGI will claim the child for EIC.

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