My adult son passed away in 2017.he was never married, no children and no will. Who files his income tax? What if he owes money?

[me530]

Who’s responsible for this?

[CarolynM · Accepted solution]

If he had no will, you are his default heir as his parent. 

You may file his tax return on his behalf.  However, if he owes tax, you are not responsible for paying. 

For more information, follow this link: IRS on Deceased Taxpayer

I am sorry for your loss.