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. The TurboTax product will need to be purchased under each account.
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). There is only one fee per download/CD.
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