S.D. Codified Laws § 3-12C-514
A member shall receive credited service for leave of absence due to qualified military service, authorized in advance by the employer, without contribution by the employee or employer if the member returns to the employ of a participating unit within one year from the member's date of discharge from the member's initial period of qualified military service and if the member remains in the employ of a participating unit for at least one year. The member may not receive credited service for any voluntary extension of qualified military service at the instance of the member beyond the initial period of enlistment, induction, or call to active duty. Credited service granted under this section shall be only for the initial period of time that the member is performing qualified military service. No credited service granted under this section may be considered to represent either member contributions or employer contributions for purposes of contribution withdrawals pursuant to this chapter.
If the member returns to the employ of the member's employer unit within one year of discharge from the initial period of qualified military service, but does not remain in the employ of the unit for at least one year, the member shall be granted credited service for the initial period of qualified military service pursuant to § 414(u)(8) of the Internal Revenue Code if the member deposits with the system employee contributions for the initial period of the qualified military service as provided for in § 414(u)(8)(C). The contributions shall be made in a lump sum, shall be based on the member's compensation immediately prior to the leave of absence, and shall be without interest. The participating unit that was the member's employer prior to the leave of absence shall deposit employer contributions in an equal amount with the system. Other provisions of this chapter notwithstanding, the member need not be a contributing member at the time the member deposits the contributions. The member is subject to the time limitations for payment provided for in § 414(u)(8)(C).
SDCL 3-12C-514