Part I—Total — Instruction 1040-SS

Line 1 Check the filing status that applies to you.

More than one filing status can apply to you.

TIP Taxpayers who aren’t married will pay the same

tax under all filing statuses for which they qualify (single, head of household, and qualifying surviving spouse). However, married taxpayers who owe additional Medicare tax on line 5 may pay less tax if they qualify for and choose the head of household filing status instead of married filing separately. You can choose the one for which you qualify that will give you the lowest tax.

Single

You can check the “Single” box if, at the end of 2025, you were unmarried or legally separated from your spouse according to your state law under a divorce or separate maintenance decree.

Married Filing Jointly

You can choose this filing status if you were married at the end of 2025 and both you and your spouse agree to file a joint tax return, even if you didn’t live with your spouse at the end of 2025. You can also choose this filing status if your spouse died in 2025 and you didn’t remarry in 2025. You can also choose this filing status if you and your spouse were married at the end of 2025 and your spouse died in 2026 before filing a 2025 return.

If you choose to file a joint tax return, check the box for married filing jointly and include your spouse’s name and SSN or ITIN on the lines provided below your name and SSN. If your spouse also had self-employment income, complete and attach a separate Schedule SE (Form 1040), Part I, and, if applicable, Part II. If necessary, attach a separate Schedule C (Form 1040) and/or Schedule F (Form 1040) for your spouse’s nonfarm and/or farm business.

Joint and several tax liability. If you file a joint tax return, both you and your spouse are generally responsible for the tax and any interest or penalties due on the tax return. This means that if one spouse doesn’t pay the tax due, the other may have to. Or, if one spouse doesn’t report the correct tax, both spouses may be responsible for any additional taxes assessed by the IRS.

However, you may qualify for innocent spouse relief from an existing tax liability on your joint tax return if:

There is an understatement of the amount of tax because your spouse omitted income or claimed false deductions or credits;
You are divorced, separated, or no longer living with your spouse; or
Given all the facts and circumstances, it wouldn’t be fair to hold you liable for the tax.

File Form 8857 to request innocent spouse relief. Some requests for innocent spouse relief may need to be filed within 2 years of the date on which the IRS first attempted to collect the tax from you. Don’t file Form 8857 with your Form 1040-SS. For more information, go to IRS.gov/ InnocentSpouse .

Nonresident aliens and dual-status aliens. Generally, a married couple can’t file a joint return if either spouse is a nonresident alien at any time during the year. However, you and your spouse can choose to be treated as U.S. residents for the entire year and file a joint return if one spouse was a nonresident alien at the end of the taxable year (the nonresident spouse) and the other was a U.S. citizen or resident at the end of the taxable year. This choice remains in effect in subsequent years until terminated. You and your spouse can also choose to file as U.S. residents for the entire year if both of you are U.S. citizens or residents at the end of the year and either (or both) of you were a nonresident at the beginning of the year (the dual-status spouse(s)). You can only make this choice for 1 year, and it does not apply to any future years.

If you and your spouse are making either of these choices to be treated as U.S. residents for 2025, check the box in Part I, Line 1 under Filing Status section and enter the name of the nonresident spouse or dual-status spouse(s) (whichever applies to you) in the entry space. Also check the box and enter their name if you and your nonresident spouse made the choice to be treated as residents in a prior year and the choice remains in effect.

To make either choice for 2025, you and your