S.D. Codified Laws § 3-12C-702
Individual’s birthday for purposes of eligibility
For purposes of determining eligibility for, and the amount of, any benefit payable pursuant to this chapter, the first day of the month in which an individual's birthday falls is considered the individual's birthday.
Source: SL 2016, ch 32, § 55; SDCL § 3-12-47.9; SL 2019, ch 22, § 1; SL 2025, ch 27, § 40.