My husband and I live in separate states but are not legally separated. Since we have to file married filing separate why do I have to itemize if he does?

[xmasbaby0]

Sorry---if you file married filing separately---for whatever reason(s)--you are subject to the tax laws as written by Congress.     If you file MFS, you both itemize or you both use standard deduction.   The IRS cross checks your returns to make sure you follow the rules and that you do not "double dip" when using itemized deductions.  

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

[MarilynG1]

You are not required to file separately because you live in different states; you still have the option to file jointly for your Federal return, and each file separate state returns.

Here's more info on Filing Separate States if you want to explore that option.

Click this link for detailed info on Married Filing Separately.

@kelliwinters72-y 

[Opus 17]

You can always file a joint return if you agree to.  If you are living in separate states, it is usually allowed to file a joint federal return and separate state returns, to avoid having each spouse's income taxed in the state where they don't live.  This is a little more complicated than a regular tax return, if you want help with this, let us know and tell us which states.  If you file a joint federal return, you don't to worry about the special rules and limitations for married filing separately.

However, if you decide to file separate federal and state returns, then you must both itemize if one itemizes, even if you don't have enough deductions.  That's how Congress wrote the law.