An appeal from the local board of equalization to a county board of equalization shall be perfected by mailing or by filing a written notice of appeal with the county auditor on or before the first Tuesday in April. If perfected by mailing, the postmark shall be conclusive evidence regarding the timeliness of the appeal. Appeals made pursuant to § 10-11-27 shall be perfected by filing a written notice of appeal with the county auditor on or before the first Tuesday in April. The county auditor shall file a copy of the notice of appeal with the appropriate clerk of the local board of equalization prior to the hearing of the appeal by the county board of equalization.
SDCL 10-11-23