If you are using TurboTax Online you can only prepare and file
one return per account. If you need to prepare another return, another
account will need to be used/created. You can create up to 5 accounts with the same email address.
If you are using TurboTax Desktop
you can prepare and e-file up to 5 federal returns and you can prepare 1
state return (there is an additional fee to e-file the state return).
https://ttlc.intuit.com/replies/3288574
