S.D. Codified Laws § 32-5-42
Any motor vehicle that is the property of this state, the United States, a county, a township, a municipality, an improvement district as defined in § 7-25A-1, a public or nonpublic school accredited by the Department of Education, an Indian mission school in this state, an Indian tribe, a fire department, a licensed ambulance service, or any bus or van owned by a church may be registered upon application, in the manner provided for other motor vehicles. However, the custodian of the vehicle shall make the application directly to the department. No fees may be charged for the registration of the vehicle. The department, upon payment to it of the actual cost of the plates, shall furnish number plates for the vehicle. All costs collected under the provisions of this section shall be deposited in the license plate special revenue fund. If the vehicle is used for a private business use or as a commercial motor carrier as defined in § 32-9-1, the operator shall secure vehicle registration pursuant to chapter 32-9 for such use.
SDCL 32-5-42