If I’m married and I’m filing separately, then why does it need my wife’s info?

[DoninGA]

Because the IRS requires you to provide your spouse's name and Social Security number on your tax return when Married and filing Separately.

However, if you live in a community property state it becomes more complex.

See this TurboTax support FAQ - https://ttlc.intuit.com/turbotax-support/en-us/help-article/taxation/married-filing-separately-commu...

[xmasbaby0]

If I am filing a separate return why do I have to list my spouse’s information on my return?

Even if you file separate returns (the worst way to file) you each have to list each other's SSN's and some other information on your own tax return.  The IRS can then cross check to make sure you are not "double dipping" for itemized deductions, dependents, etc.

If you are in a community property state, there is more information that will be needed.

Community property states:  AZ, CA, ID, LA, NV, NM, TX, WA, WI

https://ttlc.intuit.com/questions/1901162-married-filing-separately-in-community-property-states

https://turbotax.intuit.com/tax-tips/marriage/five-tax-tips-for-community-property-states/L4jG7cq7Z