Where do I add interest income from the IRS. There isn't a 1099, just a letter from them

[maarestad]

It's just $15.35 interest from the IRS. I didn't see an area for common interest

[SteamTrain]

You enter it in the same 1099-INT place as if you did get one form any otehr provider

On the page that wants you to select or enter a bank ?  ...... you don't ...instead you click on

"Change how I enter my form" at the bottom of that page.

.......and then on the next page you click on

"Type it in myself"

then you are off and running....enter as being provided by the US Treasury  (and you don't need an EIN or account number)