Amended tax returns and Form 1040X


While many people think taxes are a “set it and forget it” task—this is not actually the case. In fact, if you find errors or you left out information on your original return, you can use Form 1040X: Amended Tax Return to file a corrected version of your federal return.

What are the benefits of filing an IRS amended return?

1040X amended tax returnBelieve it or not, using an amended return can result in major benefits such as:

  • Claiming a tax credit
  • Taking a deduction you missed
  • Reporting additional income and withholding

In fact, by filing the 1040X form for an amended return, you might:

  • Receive an additional refund; or
  • Owe additional taxes as a result of the correction.

If you’re due a refund, the IRS will send it to you after it accepts your amended return. If you owe tax, send the amount owed to the IRS along with the 1040X tax form. If you owe interest or a penalty, the IRS will bill you.

What to look for when you file the 1040X form

When you amend a return for a specific reason, it’s a good idea to review your entire original return. Look for the following things you might have missed the first time around, like:

  • Deductions
  • Credits
  • Exemptions
  • Income
  • Withholding

When you do this, you might wind up owing less money or getting more of a refund.

Who can file an amended tax return using Form 1040X?

You can amend your taxes as long as your original tax return was prepared using Form 1040 or 1040SR.

What to include in your amended return

When you file a 1040X tax form, you might wonder what to include in your amended return. You’ll need to attach these items if you need to prove the changes on your amended return:

  • A copy of the federal refund deposit slip
  • Any previously unsubmitted W-2 or 1099 forms
  • Any other substantiating forms, schedules, or documentation supporting the amended return

To file an amended tax return, you can either e-file or download a paper Form 1040X from You must mail the paper form if you choose to paper file. You can also do so with the help of H&R Block, with our various filing options and products.

Due date for filing Form 1040X

To obtain a refund, you usually must file an amended return by the later of these dates:

  • Within three years from the date you filed your original return
  • Within two years from the date you paid the tax

If you received an extension, the filing date is one of these:

  • Actual date you filed your return within the extension period
  • Tax deadline if you filed your return after the extension period expired

If you’re filing an amended tax return due to a bad debt or a worthless security, you have more time to file. In this case, you have seven years after your original return’s due date to file the amended return.

If you’re a business owner, you can also file an amended tax return for a year when you carried a net operating loss (NOL). You must file the amended return within three years of the due date of the return for the NOL year.

The IRS usually has three years to assess additional taxes. However, longer periods are allowed for significant underreporting of income and fraud.

Needing to file a tax amendment? Get help.

If you’re unsure of whether or not you need to make a tax amendment, we can help. Our Second Look® tax review is free. Schedule a time to visit your local H&R Block office to put your wondering to rest.

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