Qualifications

To qualify for EITC, you must have earned income either from an employer or via selfemployment. You must also have a valid social security number and be a U.S. citizen or resident alien. (Non-resident aliens married to U.S. citizens must file a joint return.) Also, you may not file separately if you are married.

Limitations

You may not exceed certain thresholds for your adjusted gross income in order to claim this credit. For tax year 2009, those amounts ranged from $13,440 (single filer with no qualifying children) to $43,279 (single filer with three or more qualifying children). Thresholds are increased for those filing jointly. Investment income may not exceed $3,100.

Forms

You need form 1040X to amend your tax return. You will also need a copy of your originally filed 1040, 1040A or 1040EZ for reference. You will enter your original and adjusted amounts on line 13 of form 1040X for EITC.

Benefit

If you are entitled to this credit, but failed to claim it, it’s worth your time to file an amendment. The EITC is refundable and ranges from $457 to $5657 depending on your income and other factors.

Other Considerations

If you filed for this credit after tax year 1996 and were disallowed or had your credit reduced (for reasons other than math errors), you will also need to file Form 8862. You may be ineligible for 2 to 10 years, depending on the disallowance reason.