You are correct that there can definitely be tax implications related to this form.
Unfortunately, TurboTax doesn't support it at all. The only way to include it in a tax return prepared in TurboTax would be to override tax calculations, which is something we do not recommend. Overriding tax calculations also voids our Accuracy Guarantee.
Calculations can only be overridden in the forms mode of the CD/Download version of the TurboTax program. You should carefully follow the instructions for Form 8621 - for example, you may need to write in "1291 Tax" on line 11a per instructions for 16e of 8621 in some instances.
Years in which you are required to file a tax return, you attach your Form 8621 and file it along with your return to the service center that normally processes your tax return. If you are using TurboTax, you will not be able to e-File your return.
If you are not otherwise required to file a tax return, you send the form to Internal Revenue Service Center, Ogden, UT 84201-0201. Do not send it to the Odgen office if you are filing it with a return.
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"
