The NC D400V form is for your Balance due for 2016 taxes. That is used if you send a check in to the NCDOR to pay your balance due for the tax return you just prepared. Optionally, you can instead go to the NCDOR payment website and pay it online that way instead and dump the d400V.
http://www.dornc.com/electronic/d400v.html
__________________________________
The NC40 forms are quarterly estimated 2017 "Pre-Payments" for next year's taxes. IF you don't expect to owe as much next year, or are going to increase your withholding to avoid a Balance Due next year, then you could shred them (NC doesn't know they were prepared/printed)
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
