Do I need to put ex-spouse's SSN on return if divorced in 2018 & I am claiming refund from 2017 applied to 2018 + quarterly estimateds? If so where/how? (filing single)

[turboNancy2]

He was always listed first on our joint returns even though I was the wage earner & had far more in unearned income. Note we are in agreement that 2017 refund & all estimated payments belong to me.

[Carl]

The only two times the spouses SSN is required on a tax return is if:

a - you are filing a joint return, or
b - you are filing a "married filing separate" return.

If your status was not "legally married" on Dec 31 of 2018, then your file status choices are single, or head of household "if" you have a qualifying dependent that lived in your household in 2018. (I know you already know that. Just stating the obvious for clarity)

If you are using the same account that was used to prepare your joint return for 2017, and you were not listed first on that 2017 return or;

If you used the CD/Desktop version of TurboTax and were not listed first on the 2017 return, then;

Do not import "anything" from the 2017 return into your 2018 return. Otherwise, the imported data will be assigned to the wrong person and when you delete the 2nd person on the 2018 return (which would be you) all the imported data associated with that 2nd person will be deleted too.

[Anonymous]

from IRS Publication 505

Divorced Taxpayers

If you made joint estimated tax payments for 2018 and you were divorced during the year, either you or your former spouse can claim all of the joint payments, or you each can claim part of them. If you can’t agree on how to divide the payments, you must divide them in proportion to each spouse's individual tax as shown on your separate returns for 2018. If you claim any of the joint payments on your tax return, enter your former spouse's social security number (SSN) in the space provided at the top of page 1 of Form 1040. If you divorced and remarried in 2018, enter your present spouse's SSN in that space. Enter your former spouse's SSN, followed by “DIV,” under Payments to the left of Schedule 5 (Form 1040), line 66.

if TT won't let you do this, you'll need to paper file. 

[turboNancy2]

Thank you.  I did not remarry in 2018 so I entered ex spouses's first name and last name followed by "(DIVORCED in 2018)" plus his SSN on 1040 p.1 where it says "If joint return, spouse's first name and initial."  But previous answer to my question says to only enter a spouse SSN if married.  Can you advise?