! — Instruction 1040-X — Instructions for Form

CAUTION

For information about marital status, see Pub. 501, Dependents, Standard Deduction, and Filing Information.

In general, you can’t change your filing status from a joint return to separate returns after the due date of the original return.

Enter the calendar year or fiscal year you are amending.
Complete name, current address, and SSN (or ITIN, if applicable).

Changing from a separate to a joint return. If you are married and file a separate return, you generally report only your own income, deductions, and credits. Generally, you are responsible only for the tax on your own income. If you file a joint return, both you and your spouse (or former spouse) are generally responsible for the tax and interest or penalties due on

Complete Part II—Explanation of Changes.

You are changing from a separate to a joint return. If you and your spouse are changing from separate returns to a joint return, follow these steps.

6 Instructions for Form 1040-X (Rev. December 2025)

Enter in column A the amounts from your return as originally filed or as previously adjusted (either by you or the IRS).
To determine the amounts to enter in column B, combine the amounts from your spouse’s return as originally filed (or as previously adjusted) with any other changes you or your spouse is making. If your spouse didn’t file an original return, include your spouse’s income, deductions, credits, other taxes, etc., in the amounts you enter in column B.
Read the instructions for column C to figure the amounts to enter in that column.
Both of you must sign and date Form 1040-X.

You are changing amounts on your original return or as previously adjusted by the IRS. Because Form 1040-X can be used for so many purposes, it is sometimes difficult to know which part(s) of the form to fill out. Unless other specific instructions or rules apply to your return, such as those under Resident and nonresident aliens , earlier, applicable to paper filers, follow the rules below when completing your Form 1040-X.

Line 1	A. Original amount	B. Net change	C. Correct amount
Line 1	21,000	500	21,500

You would also report any additional federal income tax withheld on line 12 in column B.

See the tax return for the year you are amending to find the

corresponding lines on your original return.

Always complete the top of page 1 through Amended return filing status.
Check a box in Presidential Election Campaign, if applicable.
Complete the lines shown in the charts under Columns A Through C below according to what you are changing.
Complete Part II—Explanation of Changes.
Sign and date the form.

Columns A Through C

Column A. Enter the amounts from your original return, unless any of the following apply.

You previously amended that return.
You were audited and changes were made to your originally filed return.
You received a notice from the IRS advising they made changes to your return.

In any of these cases, column A needs to reflect the amount to which your originally filed return was adjusted.

Example. If the IRS changed your taxable income by unreported income of $10,000, making your taxable income $100,000, then column A taxable income should be $100,000, not the originally filed amount.

Column B. Enter the net increase or decrease for each line that you are changing.

Explain each change in Part II. If you need more space, attach a statement. Attach any schedule or form relating to the change. For example, attach Schedule A (Form 1040) if you are amending a 2024 Form 1040 to itemize deductions. If you are amending your return because you received another Form W-2, attach a copy of the new Form W-2. Don’t attach items unless required to do so.

Column C. To figure the amounts to enter in this column:

Add the increase in column B to the amount in column A, or
Subtract the decrease in column B from the amount in column A.

For any item you don’t change, enter the amount from column A in column C.

Note. Show any negative numbers (losses or decreases) in column A, B, or C in parentheses.

Example. You originally reported $21,000 as your adjusted gross income on your 2024 Form 1040. You received another Form W-2 for $500 after you filed your return. Line 1 of Form 1040-X should be completed as follows.

IF you are changing only...	THEN complete Form 1040-X...
filing status	lines 1–23.
income	lines 1–23.
adjustments to income	lines 1–23.
itemized or standard deductions	lines 1–23.
qualified business income deduction	lines 4a–23.
deductions for tips, overtime, car loan interest, or seniors from Schedule 1-A (Form 1040)	lines 4a–23.
tax before credits	lines 5–23.
nonrefundable credits	lines 6–23.
other taxes	lines 6–23.
payments and refundable credits	lines 11–23.

Income and Deductions

Line 1—Adjusted Gross Income

Enter your adjusted gross income (AGI), which is the total of your income minus certain deductions (adjustments). Any change to the income or adjustments on the return you are amending will be reflected on this line.

Complete and attach any applicable forms and schedules to support the amounts you refigured.

Correcting your wages or other employee compensation. Attach a copy of all additional or corrected Forms W-2 you received after you filed your original return. Also attach any additional or corrected Forms 1099-R, Distributions From Pensions, Annuities, Retirement or Profit-Sharing Plans, IRAs, Insurance Contracts, etc., that show federal income tax withheld.

A change you make to your AGI can cause other amounts to increase or decrease. For example, depending on the tax year, changing your AGI can change your:

Credit for child and dependent care expenses, child tax credit, education credits, retirement savings contributions credit, or premium tax credit;
Allowable charitable contributions deduction or the taxable amount of social security benefits; or
Total itemized deductions. If you change your AGI, refigure the items listed above (if applicable), and any other deduction or credit you are claiming that has a limit based on AGI.

Instructions for Form 1040-X (Rev. December 2025) 7

Changing your IRA deduction. In Part II of Form 1040-X, enter “IRA deduction” and the amount of the increase or decrease. If changing from a deductible to a nondeductible IRA contribution, also complete and attach Form 8606, Nondeductible IRAs.

Line 2—Itemized Deductions or Standard Deduction

Itemized deductions. 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. If you are now itemizing your deductions instead of using the standard deduction, or you have changed the amount of any deduction, or your AGI limitations have changed any deduction, attach a copy of the corrected Schedule A to this amended return.

Standard deduction. If you are using the standard deduction, enter the amount for your filing status for the year you are amending. Remember that the standard deduction for all years can be increased for the age and/or blindness of the taxpayer(s).

Charitable deduction. If you are taking the standard deduction in 2021, you (or you and your spouse if filing jointly) may be able to claim a charitable deduction for certain cash contributions. For amended 2021 returns, any adjustments to this deduction should be made to your standard deduction amount on line 2. For adjustments to the cash charitable deduction for any year, refer to the tax return instructions for the year of the return you are amending to determine the limits on amounts of cash contributions you can claim for that year. See Pub. 526 (for the year of the return you are amending) for the definition of what qualifies as a cash contribution and for information on the types of organizations that qualify. Also see Pub. 526 (for the year of the return you are amending) for information on whether this deduction is available on your amended return.

If you had a net qualified disaster loss and you elect to

TIP increase your standard deduction by the amount of your

net qualified disaster loss, use Schedule A to figure your standard deduction. Qualified disaster loss refers to losses arising from certain disasters. For more information, see the Instructions for Form 4684 and the Instructions for Schedule A filed with your original return for the tax year of the return you are amending.

Line 4a—Qualified Business Income Deduction

See the instructions for the year of the form you are amending. Also see the instructions for Forms 8995 and 8995-A for more information for figuring and reporting your qualified business income deduction.

Line 4b—Deductions for Tips, Overtime, Car Loan Interest, and Seniors From Schedule 1-A (Form 1040)

If claiming any of these deductions, attach your Schedule 1-A. See the instructions for Schedule 1-A (Form 1040) found in the Instructions for Form 1040 for the year of the form you are amending.

Line 5—Taxable Income

If the taxable income on the return you are amending is $0 and you have made changes on Form 1040-X, line 1, 2, or 4b, enter on line 5, column A, the actual taxable income instead of $0. Enclose a negative amount in parentheses. The amounts in columns A and B can be less than zero. However, if the result for column C is zero or less, you must enter -0- in column C.

Example. You showed $0 taxable income on your original return, even though you actually had a loss of $1,000. You later discovered you had additional income of $2,000. Your Form 1040-X, line 5, would show ($1,000) in column A, $2,000 in column B, and $1,000 in column C. If you failed to take into account the loss you actually had on your original return, you would report $2,000 in column C and possibly overstate your tax liability.

Tax Liability

Line 6—Tax

Attach the schedule or form(s), if any, tha your revised tax. Don’t attach worksheets.	at you used to figure
IF you figured the corrected tax using...	THEN enter on the dotted line on line 6...
Tax Table	Table.
Tax Computation Worksheet	TCW.
Schedule D Tax Worksheet	Sch D.
Schedule J (Form 1040)	Sch J.
Qualified Dividends and Capital Gain Tax Worksheet	QDCGTW.
Foreign Earned Income Tax Worksheet	FEITW.
Form 8615, Tax for Certain Children Who Have Unearned Income	F8615.

Any changes you made to Form 1040-X, lines 1 through