Quick answerSouth Dakota sells tax lien certificates for unpaid property taxes. Lien buyers can earn Up to 10% per year, bid down — the lowest interest rate bid wins and no bid above 10% is valid (SDCL 10-23-8). Redemption: Owner may redeem at any time before a tax deed issues (SDCL 10-24-1). The certificate holder may start tax deed proceedings after 3 years from the certificate sale and within 6 years (SDCL 10-25-1); redemption does not expire until 60 days after the affidavit of completed service of notice of intent to take a tax deed is filed (SDCL 10-25-8). Sales: Annual tax certificate sale on the third Monday in December, 9 a.m.-4 p.m., at the county courthouse (SDCL 10-23-7), where the county holds a sale Governing law: South Dakota Codified Laws Chapters 10-23 to 10-25 (SDCL 10-23-7, 10-23-8, 10-24-1, 10-25-1).