Taxpayers who discover they made mistakes or omissions on their tax return can correct them by filing an amended tax return. Those who need to amend should remember these tips:

• File using paper form. Use Form 1040X, Amended U.S. Individual Income Tax Return, to correct the tax return. Taxpayers can’t file amended returns electronically. They can obtain the form on IRS.gov/forms. Mail the Form 1040X to the address listed in the form’s instructions.
• Amend to correct errors. File an amended tax return to correct errors or make changes to an original tax return; for example, taxpayers should amend to change their filing status or to correct their income, deductions or credits.
• Don’t amend for math errors, missing forms. Taxpayers generally don’t need to file an amended return to correct math errors on their original return. The IRS will automatically correct these items. In addition, taxpayers don’t need to file an amended return if they forgot to attach tax forms, such as a Form W-2 or a schedule. The IRS will mail a request to the taxpayer, if needed.
• File within three-year time limit. Taxpayers usually have three years from the date they filed the original tax return to file Form 1040X to claim a refund. Taxpayers can file it within two years from the date they paid the tax, if that date is later.
• Use separate forms for each year. Taxpayers who are amending more than one tax return must file a Form 1040X for each tax year. They should mail each year’s Form 1040X in separate envelopes to avoid confusion. Taxpayers should check the box for the calendar year or enter the other calendar year or fiscal year they are amending. The form’s instructions have the mailing address for the amended return.
• Attach other forms with changes. Taxpayers who use other IRS forms or schedules to make changes must attach them to the Form 1040X.
• Wait to file for corrected refund for tax year 2017. Taxpayers who are due refunds from their original tax year 2017 return should wait to get it before filing Form 1040X to claim an additional refund. Amended returns may take up to 16 weeks to process.
• Pay additional tax. Taxpayers who will owe more tax should file Form 1040X and pay the tax as soon as possible to avoid penalties and interest. They should consider using IRS Direct Pay to pay any tax directly from a checking or savings account at no cost.
• Track amended return. Generally, taxpayers can track the status of their amended tax return three weeks after they file, using ‘Where’s My Amended Return?’ It’s available in English, Spanish, Chinese, Korean, Vietnamese and Russian. The tool can track the status of an amended return for the current year and up to three previous years. Taxpayers who have filed amended returns for multiple years can check each year, one at a time.

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