23 Va. Admin. Code § 10-120-410
B. Penalty. If the tax, or unpaid balance of the tax, is not paid in full when due then a penalty of five percent of the unpaid tax shall be imposed. No penalty will be imposed on the late payment of a tax, or portion of the tax, if all three of the following conditions are satisfied:
C. Interest. If the penalty is imposed, interest under § 58.1-1812 of the Code of Virginia shall accrue on the unpaid tax and penalty from one month after the original due date of the return (without regard to any extensions) until paid.
If no penalty is imposed, interest under § 58.1-1812 of the Code of Virginia shall accrue on the unpaid tax from the original due date of the return (without regard to any extension) until paid.
§§ 58.1-203 and 58.1-455 of the Code of Virginia.
Derived from VR630-3-455, eff. January 1, 1985.