If you are required to mail your return, TurboTax will print a cover sheet telling you what you need to send and the address to mail it too.
You will mail the Federal and state returns to separate addresses. Remember to sign and date both, or you may receive them back from the IRS or state Department of Revenue. Attach to the returns, copies any W2s, 1099Rs, and any other form with withholding.
You can sometimes go through the state or Federal returns so that you can e-file the returns. I recommend looking at why the return is required to mail in and see if you can correct the issue and e-file.
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