I need to add a 1099 int to my taxes that are already filed

[DawnC0 · Accepted solution]

If it has already been accepted, you are going to have to amend your return.  If it's rejected for any reason, then you can add the 1099 before you resubmit.

The amendment software (for 1040X) will not be ready until February but TurboTax will walk you through the amendment process.  You are going to want to wait until you have actually received your refund before you start the amendment because if there are any other issues in your return or forms that come up while the IRS is processing your return, you do not want to amend multiple times.

During the amendment process, you will be prompted with a list of items you would like to add and 1099 will be one of them.