S.D. Codified Laws § 20-13-21
It is an unfair or discriminatory practice for any person, bank, banking organization, mortgage company, insurance company, or other financial institution or lender to whom application is made for financial assistance for the purchase, lease, acquisition, construction, rehabilitation, repair, or maintenance of any real property or any agent or employee thereof, to discriminate against any person or group of persons, because of the race, color, creed, religion, sex, ancestry, disability, or national origin of such person or group of persons or of the prospective occupants or tenants of such real property in the granting, withholding, extending, modifying, renewing, or in the rates, terms, conditions or privileges of any such financial assistance or in the extension of services in connection therewith.
SDCL 20-13-21