After you file

Yes. Wait until your original return is completely processed and your payment is made. You will not need to amend your Illinois state return.

Because your Backdoor Roth conversion happened in February 2026, you will have a second step to complete when you file your 2026 taxes next year. In January 2027, Vanguard will send you a 1099-R for $7,491.02. You will pay taxes on the $491.02 gain on your 2026 return, but your $7,000 basis will remain tax-free thanks to the 2025 Form 8606 you are amending now.

If you want to make changes or add a document to a tax return that has already been filed and accepted by the taxing agency, you should follow these guidelines. 

• You must first wait until the initial return is completely processed. 
• You will have to use the same TurboTax account that you used for the original tax return. 
• Once you begin your amendment, you'll see your original return.  
• The refund calculator will start new at $0 and only reflect the changes in the refund or tax due 
• Only make changes to the areas of your return that need to be corrected. 
• You have three years from the date you filed your return or two years after you paid the tax due (whichever is later) to file an amendment 

Select your product below and follow the instructions. 

Amend TurboTax Online 

Amend TurboTax CD/Download