Get all the Facts
To file an amended return you need a copy of the original return and the information that needs to be changed.
Get all the facts before preparing Form 1040X. Begin by asking taxpayers if they have received any correspondence from the IRS making changes to the original return, or if the taxpayer has amended the return for another issue. For example, the parents of a college student correctly claimed their child as a dependent. However, their child also filed a return and incorrectly claimed the personal exemption. The child's return was processed first. In this situation, the IRS would adjust the parents' return by removing the exemption for the child. The volunteer will need this information to correctly amend the parents' and child's returns.
Research and verify that the change requested by the taxpayer is correct. For example, review the intake and interview sheet with the taxpayer and use the Volunteer Resource Guide and Publication 17.