The Rockingham County Treasurer issues tax bills which are due for payment by December 5th of each tax year. Personal property tax bills are applicable to the calendar year in which issued. The assessment is for property owned as of January 1st of each tax year. Penalty for late payment is 10% of the amount of tax owed. The Treasurer will also collect interest at an annual rate of 10% from the first month following the due date until payment is made.