If you are using a TurboTax online program, such as TurboTax Premier, you will need a separate TurboTax ID to create and file another return (plus, you will have to pay for the software again if you use the same program). For future reference, the CD/Download versions of TurboTax allow you to create more than one return and up to five e-files with the same software.
See more information on how to file another return with TurboTax online:
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