S.D. Codified Laws § 12-11-1.1 (2026)
If a vacancy occurs in the office of representative in the United States Congress due to extraordinary circumstances as defined in 2 USC Chapter 1 § 8 as of January 1, 2008, the Governor shall immediately issue a proclamation calling and setting the date for a special election to fill the vacancy. The proclamation shall contain the deadline for nomination.
Source: SL 2008, ch 65 , § 1.