Do I need to write the spouse name if I am filing for marriage separately and my spouse does not have ITIN or SSN

Yes. When you file Married Filing Separately (MFS), you must list your spouse’s name on your return, even if your spouse does not have an SSN or ITIN.

If your spouse has no SSN or ITIN, you should enter “NRA” (Nonresident Alien) in the space for your spouse’s SSN/ITIN if that applies. If your spouse is not a nonresident alien, special rules apply.  This is only appropriate if your spouse is not a U.S. citizen and does not meet the "Substantial Presence Test" (meaning they don't live in the U.S. for a significant portion of the year). In that case electronic filing isn’t allowed and you’ll need to mail-in your tax return. 

What to Enter on the Return (Form 1040)

Required fields when filing Married Filing Separately

• Spouse’s full name → Required
• Spouse’s SSN/ITIN → Required entry, but how you fill it depends on status

How to Handle the SSN/ITIN Box

Spouse is a Nonresident Alien (NRA) and has no SSN/ITIN

• Enter “NRA” in the SSN/ITIN field
• This is explicitly allowed by the IRS

Most common scenario for immigrants/new arrivals

Spouse is required to have an SSN or ITIN but doesn’t have one yet

• You cannot leave the field blank
• Options:
  
  • Apply for an ITIN using Form W-7 (often attached to the return), or
  • File an extension and submit after the ITIN is issued

Writing “Applied For” or leaving it blank can cause processing delays or rejection

Important Notes & Limitations (MFS)

When filing MFS, keep in mind:

• You generally cannot claim:
  
  • Earned Income Credit
  • Education credits (with limited exceptions)
• Standard deduction may be limited if spouse itemizes
• Community property rules may apply in certain states

Examples

Example 1 (Allowed):

• You file MFS
• Spouse lives abroad, is a nonresident alien, no SSN/ITIN
  → Enter spouse’s name and “NRA”

Example 2 (Not Allowed):

• You omit spouse’s name
  → Return may be rejected or delayed

Community Property States: If you live in a state like California, Texas, or Washington, filing MFS is significantly more complex because you may be required to report half of your spouse's income on your return, even if they aren't in the U.S.

If you file Married Filing Separately, and your spouse (even an NRA spouse) decides to file a separate U.S. return and itemizes their deductions, you are also forced to itemize. You cannot take the standard deduction if your spouse itemizes, even if you are filing separately.

Summary

Yes, you must include your spouse’s name when filing Married Filing Separately.
If your spouse does not have an SSN or ITIN:

• Enter “NRA” only if your spouse is a nonresident alien
• Otherwise, you must apply for an ITIN or delay filing

Source:

• Form 1040 Instructions (2025) - Filing status & spouse identification
• IRS Publication 519, U.S. Tax Guide for Aliens
• Form W-7, Application for IRS Individual Taxpayer Identification Number