S.C. Code Ann. § 12-37-2840: Road use fees due at the same time as registration fees.

Notwithstanding another provision of law, a motor carrier registering a large commercial motor vehicle or bus must pay to the Department of Motor Vehicles the road use fee due on the vehicle at the time and in the manner the person pays the registration fees on the vehicle pursuant to Section 56-3-660. A person choosing to pay South Carolina registration fees on a large commercial motor vehicle or bus in quarterly installments pursuant to Section 56-3-660 also must pay the road use fee on the vehicle in the same quarterly installments. The Department of Motor Vehicles must make quarterly installment payments available to a customer upon the customer's request provided that each installment payment is made online.