If your grandson filed his federal return in TurboTax Online, he can login to his TurboTax account and add a state.
Note that you can't file just a state return because TurboTax State is not available as a stand-alone program. Please see the FAQ below for more information including suggestions about how to file a state tax return if you didn't file the federal return using TurboTax.
Can I prepare and file just my state return using TurboTax?
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