S.D. Codified Laws § 10-11-42
Any owner or taxpayer feeling aggrieved by the decision of the county board of equalization relative to the assessment of its property or any taxing district or governmental subdivision or agency in which such property is located, feeling aggrieved by the decision of the county board of equalization may appeal to the Office of Hearing Examiners. An appeal to the Office of Hearing Examiners from a county board of equalization shall be perfected by mailing or by filing a notice of appeal with the chief administrative law judge, Pierre, South Dakota, no later than the third Friday in May. If perfected by mailing, the postmark shall be conclusive evidence regarding the timeliness of the appeal. The chief administrative law judge shall file a copy of the notice with the county director of equalization within ten days after receipt of notice of appeal. The county director of equalization shall file notice of appeal to the appropriate clerk of the local board of equalization prior to the hearing of the appeal by the Office of Hearing Examiners. The notice shall state informally the substance of the decision appealed from and the grounds upon which appeal is taken. The county board of equalization or any person pecuniarily interested in sustaining its decision, as well as the appellant, may be heard in person or by attorney upon appeals to the Office of Hearing Examiners. Nothing in this section prevents an appeal to the circuit court as provided in § 10-11-44, but an appeal to either tribunal excludes an appeal to the other.
SDCL 10-11-42