Instructions for Filling Out Form 1040-X

Instructions for Filling Out Form 1040-X

Written by 
Pilot Team
November 26, 2023
Instructions for Filling Out Form 1040-X

This document offers comprehensive guidance on completing Form 1040-X, which is used to amend a previously filed U.S. Individual Income Tax Return. It covers filing requirements, section-by-section instructions, and special situations, ensuring taxpayers have the necessary information to accurately amend their tax returns.

In this article, we'll provide an overview of Form 1040-X and a step-by-step guide on how to fill it out, ensuring a smooth amendment process for taxpayers.

What is Form 1040-X?

Form 1040-X is a document used by taxpayers to amend a previously filed U.S. Individual Income Tax Return, specifically Forms 1040, 1040-SR, or 1040-NR. It serves various purposes, such as correcting errors in the original tax return, making certain elections after the prescribed deadline, changing amounts previously adjusted by the IRS, claiming a carryback due to a loss or unused credit, and making certain elections after the deadline. Taxpayers should file Form 1040-X only after the original return has been filed and can file it multiple times if necessary, adhering to specific time constraints for credits or refunds.

Who Must File Form 1040-X?

Individuals who need to file Form 1040-X include those who must correct a previously filed Form 1040, 1040-SR, or 1040-NR, or change amounts previously adjusted by the IRS. Additionally, Form 1040-X can be used to claim a carryback due to a loss or unused credit, or to make certain elections after the deadline has passed.

Form 1040-X Tax Filing Deadlines and Due Dates

  • For a credit or refund, Form 1040-X must generally be filed within 3 years (including extensions) after the date the original return was filed.
  • If filing within 2 years after the date the tax was paid, it must be filed within that 2-year timeframe, whichever is later.

Form 1040-X Late Payment Penalty

While the official instructions for Form 1040-X do not provide specific information on late payment penalties, they do mention that the IRS will charge interest on taxes not paid by their due date, even if an extension of time to file was granted. Additionally, penalties can be imposed for negligence, substantial understatement of income tax, reportable transaction understatements, and fraud.

Step-by-Step Instructions for Form 1040-X

The step-by-step instructions for filling out Form 1040-X are as follows:

  1. Enter the calendar year or fiscal year you are amending at the top of the form.
  2. Complete your name, current address, and social security number (SSN) or individual taxpayer identification number (ITIN) on the front of Form 1040-X.
  3. Check the box that corresponds to your filing status on this return. You must check one box even if you are not changing your filing status.
  4. Enter your adjusted gross income (AGI), which is the total of your income minus certain deductions (adjustments).
  5. If you are using the standard deduction, enter the amount for your filing status for the year you are amending. If you itemized your deductions, enter in column A the total from your original Schedule A or your deduction as previously adjusted by the IRS.
  6. Figure the tax on your taxable income shown on line 5, column C. Generally, you will use the method(s) you used to figure the tax on your original return.
  7. Enter your total nonrefundable credits in column A. Nonrefundable credits are those that reduce your tax, but any excess isn’t refunded to you.
  8. Include on line 6 the amount you reported on Schedule 2 (Form 1040), line 3, for the year you are amending.
  9. Enter the overpayment from your original return. If your original return was changed by the IRS and the result was an additional overpayment of tax, also include that amount on line 18.
  10. If you owe tax and you don’t want to pay electronically, enclose (don’t attach) your check or money order in the envelope with your amended return.
  11. Sign and date the form. If you are filing an amended joint return, your spouse must also sign.
  12. Assemble any schedules and forms behind Form 1040-X in the order of the “Attachment Sequence No.” shown in the upper-right corner of the schedule or form.

How to Submit Form 1040-X

To submit Form 1040-X, first ensure that your original return has been filed. You can file Form 1040-X multiple times, as long as it's within the specified time constraints. Complete the form, including the top of page 1 through "Amended return filing status," checking a box in "Presidential Election Campaign" if applicable, and filling out the lines shown in the charts under "Columns A Through C" according to the changes you're making. Additionally, complete the "Explanation of Changes" section (Part II if paper filing or Part III if e-filing), sign and date the form, and follow the provided instructions on where to file your return.

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