how long before you get revenue back
1 A check from the NC Department of Revenue is valid up to 6 months after the date on the check. 2  If a check date is older than 6 months, you should mail a letter along with the refund check to NC Department of Revenue, Attn: Customer Service, P O Box 1168, Raleigh, NC 27602-1168. If a check date is older than 6 months, you should mail a letter along with the refund check to NC Department of Revenue, Attn: Customer Service, P O Box 1168, Raleigh, NC 27602-1168. 2  Your check will be validated and re-mailed to you.