Line 6 should NOT include any inherited IRA's at all. Only *your* IRA's in your name are totaled for line 6. Inherited IRA's must be kept in the name of the deceased with you as beneficiary. Any basis in a inherited IRA must be tracked separately on a separate 8606 for the inherited IRA and not your own 8606. The basis in an inherited IRA cannot be combined with your own basis.
If there is a basis in the inherited IRA then TurboTax does not support a separate 8606. You would need to download a blank 8606 form from the IRS, fill it out, and attach it to a mailed tax return.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
