35 Miss. Code R. § 4-11-02-701
A vehicle furnished free of charge or at less than an arms-length charge is taxable to the dealer on the value of the vehicle when withdrawn from stock. This includes cars used by owners, salesmen, dealership employees, or any other individual whom the dealership has given a car for use. The value of the vehicle shall be determined by computing the annual lease value of the vehicle based on its fair market value (FMV) as of the first date the auto is made available for personal use. The FMV is determined to be the manufacturers invoice price. This figure should then be used to determine the annual lease value assigned by the Internal Revenue Service in absence of any other method of determination provided by the Department. Tax at the rate of 5% should be paid on the total lease value of all vehicles provided to individuals for personal use. No credit for tax paid on the use of the vehicle will be allowed against the tax due once the vehicle is sold. The total tax due should be computed on December 31st of each year and reported on the December sales tax return due by January 20th.
35 Miss. Code. R. § 4-11-02-701