! spouse must — Instruction 1040-SS

CAUTION statement, signed by both spouses, to your return.

To find out what information must be included in the statement, as well as more information on these choices, see Nonresident Spouse Treated as a Resident for nonresident aliens and Choosing Resident Alien Status for dual-status aliens in Pub. 519.

Married Filing Separately

Check the “Married filing separately” box if at the end of 2025 you were married, and file a separate tax return. Enter your spouse’s name in the entry space below the filing status checkboxes. Be sure to enter your spouse’s SSN or ITIN in the space for spouse’s SSN. If your spouse doesn’t have and isn’t required to have an SSN or ITIN, enter “NRA” next to their name in the entry space below the filing status checkboxes.

For electronic filing, enter the spouse’s name or “NRA” if the spouse doesn’t have an SSN or ITIN in the entry space below the filing status checkboxes.

Instructions for Form 1040-SS (2025) 7

If you are married and file a separate tax return, generally, you are responsible only for the tax on your own income. However, you will usually pay more tax than if you use another filing status for which you qualify.

You may be able to file as head of household if

TIP you had a child living with you and you lived apart

from your spouse during the last 6 months of 2025.

Head of Household

A head of household is someone who is unmarried (or is considered unmarried) and provides a home for certain other persons.

If you owe Additional Medicare Tax on line 5, were

TIP married at the end of 2025, but lived apart from

your spouse for the last 6 months of 2025 and do not claim a qualifying child for the ACTC, see Head of Household in Pub. 501, Dependent, Standard Deduction, and Filing Information, for additional rules for this filing status.

You can check the “Head of household” box if, at the end of 2025, you are unmarried (or are considered unmarried), claim a qualifying child for the ACTC, and paid over half the costs of keeping up a home in which you lived with your qualifying child.

You are considered unmarried for this purpose if any of the following applies.

You were legally separated according to your state law under a decree of divorce or separate maintenance at the end of 2025. But if, at the end of 2025, your divorce wasn’t final (an interlocutory decree), you are considered married.
You are married but lived apart from your spouse for the last 6 months of 2025 and you meet the other rules under Married persons who live apart , later.
You are married and your spouse was a nonresident alien at any time during the year and the election to treat the alien spouse as a resident alien is not made.

Qualifying child. A child you claim for the ACTC is a qualifying child for this filing status. Your adopted child is always treated as your own child. See Qualifying child, later. However, don’t include as your qualifying child for this filing status any child you claim for the ACTC because of the rule for Children of divorced or separated parents (or parents who live apart) in Pub. 501 or under a multiple support agreement. See Qualifying Child of More Than One Person in Pub. 501.

Married persons who live apart. Even if you weren’t divorced or legally separated at the end of 2025, you are considered unmarried if all of the following apply.

You lived apart from your spouse for the last 6 months of 2025. Temporary absences for special circumstances, such as for business, medical care, school, or military service, count as time lived in the home.
You file a separate tax return from your spouse.
You paid over half the cost of keeping up your home for 2025.
Your home was the main home of your child, stepchild, or foster child for more than half of 2025. If the child didn’t live with you for the required time, see Temporary absences in Pub. 501.
You can claim this child as your dependent or could claim the child except that the child’s other parent can claim the child under the rule for Children of divorced or separated parents (or parents who live apart) in Pub. 501.

Foster child. A foster child is any child placed with you by an authorized placement agency or by judgment, decree, or other order of any court of competent jurisdiction.

Qualifying Surviving Spouse

You can check the “Qualifying surviving spouse” box if all of the following apply.

Your spouse died in 2023 or 2024 and you didn’t remarry before the end of 2025.
You have a child or stepchild (not a foster child) whom you can claim as a dependent or could claim as a dependent except that, for 2025:

a. The child had gross income of $5,200 or more,

b. The child filed a joint tax return, or

c. You could be claimed as a dependent on

someone else’s tax return.

If the child isn’t claimed as your dependent, enter the child’s name in the entry space below the filing status checkboxes. If you don’t enter the name, it will take us longer to process your tax return.

This child lived in your home for all of 2025. If the child didn’t live with you for the required time, see Temporary absences in Pub. 501.
You paid over half the cost of keeping up your home.
You could have filed a joint tax return with your spouse the year your spouse died, even if you didn’t actually do so.

If your spouse died in 2025, you can’t file as qualifying surviving spouse. Instead, see Married Filing Jointly , earlier.

Qualifying child. A child or stepchild (not a foster child) you claim for the ACTC is a qualifying child for this filing status. Your adopted child is always treated as your own child. See Qualifying child , later. However, don’t include as your qualifying child for this filing status any child you

TIP

The qualifying children you claim for the ACTC are those you list by name and SSN in the qualifying children section on Part I, line 2, of Form 1040-SS.

Keeping up a home. To find out what is included in the cost of keeping up a home, see Keeping up a home in Pub. 501.

8 Instructions for Form 1040-SS (2025)

claim for the ACTC because of the rule for Children of divorced or separated parents (or parents who live apart) in Pub. 501 or under a multiple support agreement. See Qualifying Child of More Than One Person in Pub. 501.

(from Form 4137, line 13). Attach a completed Form 4137 to your return.

Line 6b

Uncollected employee social security and Medicare tax on tips. If you didn’t have enough wages to cover the social security and Medicare tax due on tips you reported to your employer, the amount of tax due should be identified with codes A and B in box 12 of your Form W-2AS, W-2CM, W-2GU, or W-2VI; or entered in boxes 25 and 26 of your Form 499R-2/W-2PR. On Part I, line 6b, enter the amount of this tax.

Line 6c

Uncollected employee social security and Medicare tax on wages. If you’re an employee who received wages from an employer who didn’t withhold social security and Medicare tax from your wages, complete Form 8919 to figure your share of the unreported tax. On Part I, line 6c, enter the amount of tax due (from Form 8919, line 13). Attach the completed Form 8919 to your return.

Line 6d

Uncollected employee social security and Medicare tax on group-term life insurance. If you had group-term life insurance through a former employer, you may have to pay social security and Medicare tax on part of the cost of the life insurance. The amount of tax due should be identified with codes M and N in box 12 of your Form W-2AS, W-2CM, W-2GU, or W-2VI. If you are a bona fide resident of Puerto Rico, contact your employer for this amount. On Part I, line 6d, enter the amount of this tax.

Line 8 Enter any estimated federal income tax payments you made for 2025, including any overpayment from your 2024 tax return that you applied to your 2025 estimated tax.

If you or your spouse made separate estimated tax payments but are now filing a joint return, add the amounts you each paid and enter the total on line 8. If you and your spouse made joint estimated tax payments but are now filing separate tax returns, you can divide the amount paid in any way you choose as long as you both agree. If you can’t agree, you must divide the payments in proportion to each spouse’s individual tax, as shown on your separate tax return for 2025. For an example of how to do this, see Pub. 505, Tax Withholding and Estimated Tax. Show both SSNs in the space provided on the separate returns.

Divorced taxpayers. If you got divorced in 2025 and you made joint estimated tax payments with your former spouse, enter your former spouse’s SSN in the space provided on line 8. If you were divorced and remarried in 2025, enter your present spouse’s SSN in the space provided on the front of Form 1040-SS.

Name change. If you changed your name and you made estimated tax payments using your former name, attach a statement to the front of Form 1040-SS that explains all

TIP

The qualifying children you claim for the ACTC are those you list by name and SSN in the qualifying children section on Part I, line 2, of Form 1040-SS.

Dependent. To find out if someone is your dependent, see Dependents in Pub. 501.

Keeping up a home. To find out what is included in the cost of keeping up a home, see Keeping up a home in Pub. 501.

Line 2 Enter the name and SSN for each qualifying child for which you are claiming the ACTC. See Qualifying for the Credit under Part II—Bona Fide Residents of Puerto Rico Claiming Additional Child Tax Credit, later, to find if your child is a qualifying child.

You cannot take the credit for other dependents