1) IF you E-filed your state tax return, and it was accepted, then you don't need to do anything else.
2) IF you selected mail-filing for your entire NC tax return, then you do need to mail in the NC forms, along with any W-2 and 1099-R forms...and any that show any NC withholding on them. You wouldn't need to send in the D-400V voucher since you already paid online.
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Complications: If you paid taxes due using the NC online payment website...AND If you e-filed your NC tax return, AND provided bank information to D.Debit from your bank when you e-filed...? then you may have double-paid. NC would eventually refund you the excess, but it might take a couple weeks-to-months for them to catch up.
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Note that entering bank information for a Federal payment-due does not automatically get applied to a state payment due...the bank info has to be entered entirely separately for each filing.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
