S.D. Codified Laws § 3-13-72 (2026)
No contributions other than a designated Roth contribution and a properly attributable investment return may be credited to a participant's designated Roth account. The plan must maintain separate recordkeeping for each designated Roth account and must record the year that the participant first made a designated Roth contribution.
Source: SL 2025, ch 27 , § 99.