You do not amend a return that was never filed in the first place. Amending is a special process one only uses for a return that has been filed with mistakes that has been fully processed by the IRS--that is not your situation, You need to file a 2016 return that was never filed at all.
Either your 2016 return was not filed or your return was rejected and you did not notice and follow up to re-file it. If you used TurboTax you can look for the return in your account. It will have to be printed signed and mailed. It cannot be e-filed.
If you just flat out did not prepare a 2016 return then you can still do so:
To file a return for a prior tax year
If you need to prepare a return for 2016, 2017, or 2018 you can purchase and download desktop software to do it, then print, sign, and mail the return(s)
https://turbotax.intuit.com/personal-taxes/past-years-products/
Remember to prepare your state return as well—if you live in a state that has a state income tax.
When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS/state received the return.
Note: The desktop software you need to prepare the prior year return must be installed/downloaded to a full PC or Mac. It cannot be used on a mobile device.
If you are getting a refund, there is not a penalty for filing past the deadline. If you owe taxes, the interest/penalties will be calculated by the IRS based on how much you owe and when they receive your return and payment. The IRS will bill you for this; it will not be calculated by TurboTax.
https://ttlc.intuit.com/questions/1900990-how-do-i-file-a-prior-year-tax-return
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
