Can I sign as surviving spouse if my deceased husband and I are filing Married Filing Separately?

[DoninGA]

If your spouse passed away in 2017 why are you not filing as Married Filing Jointly?

[cynthiav2006]

We did not live together in 2017 and it was financially better to file separate.

[DoninGA]

Yes you can sign the tax return as Surviving Spouse on the Married Filing Separately tax return if the spouse passed in 2017 and you are filing the 2017 tax return.
You can sign the return for your spouse and enter “Filing as surviving spouse” in the area where you sign the return..  At the top of the tax return write in "Deceased"
Are you using the TurboTax online editions to complete the tax return for the deceased spouse?

[fanfare]

You may sign as Personal Representative, assuming you are the executor of his estate.