Mom passed away in 2018. She is not due a federal refund. She is due a refund from Oklahoma. Which form do I need to fill out to request her refund from Oklahoma? There is no estate or probate.
You can fill out a regular OK Form 511.
In the Personal Info section, mark her as Deceased with her date of death (screen shot attached), and the information will carry to your OK return.
To make sure, check to see if the box to the right of her social security number on page 1 of her 2018 Form 511 paper copy is checked before submission.