It is better for you to Amend your tax return rather than wait for the IRS to send a bill. This is because it usually takes the IRS over a year to match up the tax forms to your return and by that time you will owe interest and penalties on top of the tax.
If you have already filed your returns and they have been Accepted, you will first need to wait until the IRS fully processes your return and you receive your refund.
Next, you will need to Amend your Tax Return by filing Form 1040-X to include your Forms 1099-R and 1099-INT.
You can click here for instructions on Amending your tax return: How to Change a Tax Return You Already Filed. TurboTax will walk you through Amending your State Tax as well.
The 2018 Form 1040-X is estimated to be available February 14, 2019. You can click here for information on IRS Forms Availability.
Note: You SHOULD NOT make any changes on your return in TurboTax until this form becomes available.
