What do you mean upload a tax return?
If you are using the TurboTax online editions, as suggested by your post, you can Download the PDF of your tax return after the TurboTax account fees have been paid with a credit card or you have e-filed the federal tax return and it has been Accepted by the IRS.
To access your current or prior year online tax returns sign onto the TurboTax website with the userID you used to create the account - https://myturbotax.intuit.com/
Scroll down to the bottom of the screen and on the section Your tax returns & documents click on Show. Click on the Year and Click on Download/print return (PDF)
This not useful. I'm being recommended by Intuit to look at past returns in order to access past information, which are in "Your tax returns & documents", but I don't know where those are. I've been using TurboTax a *long* time, and have been interacting through Intuit to file taxes for a long time, too.
E.g.,
There's no such place "Your tax returns (ampersand) documents" when I log into Intuit.
Many people have multiple TT accounts and forget how to access them. Log out of the account you are in now.
Account recovery
https://myturbotax.intuit.com/account-recovery/
https://ttlc.intuit.com/questions/1901535-forgot-your-turbotax-online-user-id-or-password
Or did you use the desktop version of TurboTax? If so, the files are on your own hard drive or any backup device you used like a flash drive.
https://ttlc.intuit.com/questions/1901486-how-many-turbotax-accounts-do-i-have
https://ttlc.intuit.com/questions/1901535
https://ttlc.intuit.com/questions/1901659-find-your-tax-data-file-in-mac
https://ttlc.intuit.com/questions/1900721-find-your-tax-data-file-tax-file-in-windows
To get a copy of your previously filed returns prepared with online TurboTax https://ttlc.intuit.com/questions/1900748-how-do-i-get-a-copy-of-a-return-i-filed-in-turbotax-online
@ SDTaxed
What are you doing? Are you trying to find your prior online returns to review?
Are you referring to Online TurboTax or the desktop software (CD/download)? If your prior returns were prepared in Online TurboTax, here's how to find them. If you don't find evidence of the prior returns in that account, we can tell you how to look for multiple accounts. Many people end up with multiple accounts without realizing it.
If you are using Online TurboTax, log in and at the Tax Home scroll down near the bottom of the page to "Your Tax Returns & Documents". Expand that section and choose the prior tax year you want. Then you can "download/print the PDF." Or if you just need the 2018 AGI, there may be a link there for the 2018 AGI.
See image:
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@SDTaxed wrote:It worked, eventually. Thank you, all!
Good news! You're welcome. Good luck.