At this time, there is no way to link or merge those two accounts if you have different usernames and passwords for each of them. Please see below for more details on why this measure is in place.
Note: If your Mint and TurboTax accounts have different user IDs/passwords, you won’t be able to import from Mint. However, you may still be able to import the same documents into TurboTax directly from your financial institutions (and keep the benefit of any potential year-over-year transfer in your already existing TurboTax account).
Can I merge my accounts?
Other Related Topics:
Do I need to create a new TurboTax account if I want to import from Mint?
How do my Mint and TurboTax accounts work together when importing?
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