You should file an amended return if your filing status, your dependents, your total income or your deductions or credits were reported incorrectly.
In some cases, you do not need to amend your tax return. The IRS usually corrects math errors or requests missing forms – such as W-2s or schedules – when processing an original return. In these instances, do not amend your return.
Use IRS form 1040x to report tax return amendments.
