S.D. Codified Laws § 58-18-92

If not otherwise provided, a multiple employer trust doing business in this state on a self-funded basis shall pay premium taxes as required in chapter 10-44 based upon the amount each participating employer contributes, including any amounts contributed by employees and dependents, to the plan on an annual basis. If a multiple employer trust purchases excess or stop loss coverage, the multiple employer trust may not be taxed additionally for that coverage.