If you're using the online software and you used online software last year, then all you need to do is login to the same account. The following FAQ has a lookup tool if you need help finding the right account.
If you're using Desktop software this year, click HERE if you use Windows or HERE if you use Mac.
Last year I used the pc software on my computer. This year I want to use the online version. How do I bring last years info into this year's return? I have the saved PDF file still on my computer which has several "carry-overs" ?
You can transfer information into TurboTax Online from a PDF produced by other software, but not from a TurboTax PDF. If you used TurboTax last year you have to transfer from the .tax2019 file, not from a PDF. If you used TurboTax Online last year, and you use the same account this year, the transfer is done automatically.
See the following FAQ for details about transferring information from last year's tax return into TurboTax Online for 2020.
How do I transfer last year's return into TurboTax Online?
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