So sorry for your loss. Instead of "assuming" anything about how your father's widow filed a tax return, you should ask and find out for sure. For the year that your dad died, his spouse is permitted to file a joint tax return if she wants to---thereby getting the married filing jointly standard deduction which means she pays less tax on their income. If she filed married filing separately, then your dad's return should also use the MFS filing status. But....find out. If she already filed a joint tax return for 2024, then you will not need to file an individual return for him. If there is a separate "estate" return to prepare and file you will need to use desktop TurboTax Business for that.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
