S.D. Codified Laws § 3-9-1
In lieu of actual transportation expenses and except as provided in § 3-9-1.1, the mileage reimbursement rate for using a privately owned motor vehicle on state business is fifty-one cents per mile or the standard mileage rate for business authorized by the United States Internal Revenue Service as of October first each year, whichever is greater. However, if no state vehicle is equipped for the transportation of a person with special needs, the mileage reimbursement rate for using a privately owned motor vehicle is based on the type of vehicle. If a privately owned passenger or cargo van, pickup truck, or sport utility vehicle is used to transport an individual with special needs for state business, the mileage reimbursement rate is sixty-eight cents per mile or one-hundred-and-thirty percent of the standard mileage rate for business authorized by the United States Internal Revenue Service as of October first each year, whichever is greater. If any other vehicle is used to transport an individual with special needs for state business, the mileage reimbursement rate is fifty-one cents per mile or the standard mileage rate for business authorized by the United States Internal Revenue Service as of October first each year, whichever is greater. For the purposes of this section, the term "individual with special needs" means a person with a disability that makes the person unable to operate an unmodified motor vehicle but allows the person to operate a personal motor vehicle modified to accommodate the disability.
The mileage reimbursement rate covers all expenses incidental to the operation of a motor vehicle.
The Bureau of Finance and Management shall publish in writing the mileage reimbursement rate to be effective as of October first each year. The state auditor shall issue warrants for using a privately owned motor vehicle on state business at the rate specified upon the sworn statement of the party using the vehicle.
SDCL 3-9-1