My husband and I have a disabled son. We've been separated for two years. I want to file head of household. Last summer, he agreed to platonically rent from me to help care for my son. Did we "live" together?

[VolvoGirl]

If you are married you can't file Single.   You can file Married filing Separate or Head of Household if you qualify.

Does he live with you or not?  Why aren't you filing a Joint return?

Unless you have a specific reason to file separate returns,

It is usually better to file Joint. Joint has the lowest tax rates and the highest Standard Deduction.   And if you are in a Community Property state MFS gets tricky to figure out.  Here's some things to consider about filing separately……

In the first place you each have to file a separate return, so that's two returns.  And if you are using the Online version that means using 2 accounts and paying the fees twice.  

Many people think they come out better when filing Married Filing Separate but they are probably doing it wrong.  If one person itemizes deductions then the other one must itemize too, even if it's less than the standard deduction, even if it is ZERO!  

And there are several credits you can't take when filing separately, like the

EITC Earned Income Tax Credit

Child Care Credit

Educational Deductions and Credits

And contributions to IRA and ROTH IRA are limited when you file MFS.

Also if you file Married Filing Separately up to 85`% of your Social Security becomes taxable right away even with zero other income.

See …….

https://ttlc.intuit.com/community/married/help/is-it-better-for-a-married-couple-to-file-jointly-or-...

[Magnify6]

We were separated for two years prior to this, but I couldn't retain staff through covid.  

[GeorgeM777]

Yes, it appears that you and your husband did in fact live together because, as you have indicated, your husband lived in your home even though he paid you rent.  It does not appear that the IRS would consider you to be "unmarried" as you have not obtained a final decree of divorce or separate maintenance, or a decree of annulment.  Thus, if you wish to file a return and not include your spouse on your return, your proper filing status would not be single, because you are still considered married under IRS rules.  You might consider the filing status of "married filing separately."  

Given your situation, it does not appear that Head of Household (Head of Household will provide for a greater standard deduction amount versus Married Filing Separately) would be an option for you either.  Although, it appears that you might not have considered all of your options.  In this regard, here is a TurboTax article that explains the various filing statuses which you might find useful.  At the bottom of this article are other links to articles which discuss the filing status for Married Filing Jointly, Married Filing Separately and Head of Household.  You might find these articles helpful also.  

What Is My Filing Status