In TurboTax
Online, you can prepare and e-file one federal and up to five associated
state returns under the same login.
You can also
e-file up to five federal returns for each email address tied to a TurboTax
account, but you must create a separate login for each return, and each return
should have a unique Social Security or Tax ID number.
The IRS
prohibits using the same email address to e-file more than five federal returns
with an online personal tax return preparation product.
