Tax Sale Research
How the St. Louis County Tax Sale Works, and What Bidders Paid
Bottom line: in all six St. Louis County tax sales from 2020 through 2025, the typical winner of a contested parcel paid at least 32% more than the next-highest bid. None of that extra money earns redemption interest. The sale that closed on 26 August 2026 is not in these figures.
How the sale works
St. Louis County sells parcels with unpaid property taxes in a sealed-bid sale. Each bidder writes one number for a parcel and hands it in. The county publishes the winner. The second-highest bid is not secret, but nobody had added it up.
The opening bid is the amount the sale was held to collect: the delinquent taxes and costs. You cannot bid below it, and you are not required to bid above it.
The 2026 sale took bids from Friday 21 August and closed at 5pm on Wednesday 26 August 2026.
What bidders paid
| Measure | Result | Sale years |
|---|---|---|
| Typical contested winner, paid above the next-highest bid | 32% in the lowest sale, 51% in the highest | 2020 to 2025 |
| Same measure in the 2025 sale | 40.3% | 2025 |
| Total paid above the next-highest bid on contested parcels | about 15.5 million dollars | 2020 to 2025 |
| Parcels in the 2025 sale that drew a single envelope | 47.3% | 2025 |
| Lone bidders in the 2025 sale who paid more than the opening bid | 228 of 243 (93.8%) | 2025 |
Why the extra money does not come back
Under RSMo 140.340, redemption interest runs on the amount the sale was held to collect. The owner who catches up pays it, not the county. A bid above that amount earns nothing, so every dollar of overpayment is gone.
What is free
The full written report is free with a Mosaic account, and you can read it as soon as you sign up. The interactive guide covers every parcel in the 2026 offering, 3,827 parcels, and it is free with a Mosaic account too. Each parcel's tax status is re-checked about once a week, and every card shows the date it was last checked.
Both sit under Exclusive research in the account menu.
How we measured this
We counted 6,177 bids on 2,735 parcel sales in the sale years 2020 through 2025. That is every bid placed, not only the winning ones. The 2,735 sales cover 2,635 different parcels, because some parcels sold in more than one year. A parcel is contested when it drew two or more bids. The amount paid above the next-highest bid is the winning bid minus the second-highest bid.
These figures cannot tell you who won or what sold at the 2026 sale, because we do not hold its results. They also cannot tell you whether a winner's parcel was later redeemed. No source we hold tracks that.