IRS Forms

IRS Form 1040-X
Submission Guide

Need to correct a tax return? Here's how to submit your amended return (Form 1040-X) to the IRS by e-file or mail.

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Fax numbers are subject to change without notice. Always verify current fax numbers and filing instructions at irs.gov or the IRS Form 1040-X page before submitting any documents.

What is IRS Form 1040-X?

IRS Form 1040-X is the Amended U.S. Individual Income Tax Return. Use it to correct errors on a tax return you've already filed — whether that's fixing your filing status, reporting additional income, or claiming deductions and credits you missed. You have three years from the original filing date to submit an amendment. For official instructions and the latest version of this form, visit the official IRS page.

How to Submit IRS Form 1040-X

Primary method: E-file or Mail

The IRS now accepts Form 1040-X electronically through tax preparation software. You can also mail it to the IRS. See the form instructions for the correct mailing address based on your state. E-filing provides the fastest processing.

Alternative: Fax

Fax is not the standard submission method for amended returns. If you have a specific IRS fax number from correspondence or your tax professional, you can fax this form using usfax.com for instant delivery confirmation.

How to Submit Form 1040-X to the IRS

1

Complete Form 1040-X

Fill in the original amounts, corrected amounts, and the difference for each line you're changing. Include a clear explanation of the changes on Part III of the form.

2

Choose your submission method

You can now e-file Form 1040-X through tax preparation software for the fastest processing. Alternatively, mail it to the IRS address in the form instructions. If you have a specific fax number from IRS correspondence, you can fax it using usfax.com.

3

Save your confirmation

Keep your e-file confirmation, certified mail receipt, or usfax.com delivery confirmation as proof of submission — you may need it if the IRS has questions about when your amendment was received.

Common Mistakes to Avoid

  • Failing to include a clear explanation of why you're amending your return in Part III — the IRS may delay processing without it.
  • Not attaching corrected schedules and supporting forms — send everything the IRS needs together.
  • Amending before your original return has been processed — wait until you receive your refund or notice before filing Form 1040-X.

Need to Fax a Form to the IRS?

If you have a fax number from your IRS representative, use usfax.com to send your form and get delivery confirmation. No fax machine needed.

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Frequently asked questions

File Form 1040-X when you need to correct errors on a previously filed tax return — such as changes to filing status, income, deductions, or credits. You generally have three years from the date you filed the original return to submit an amendment.

You can now e-file Form 1040-X using tax preparation software, or mail it to the IRS. E-filing is faster and provides electronic confirmation. Fax is not a standard submission method for amended returns.

The IRS typically takes 16 weeks or more to process Form 1040-X. You can check the status using the IRS 'Where's My Amended Return?' tool at irs.gov starting 3 weeks after submission.

Yes. Include any new or corrected forms and schedules that support the changes on your amended return. If e-filing, your tax software will guide you. If mailing, include all supporting documents in the same envelope.

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