When the sale is held
Not applicable. There is no certificate sale and no bidder. On September 1 each year the county treasurer issues one tax certificate to the county covering every parcel in the tax roll whose real property taxes, special assessments, special charges or special taxes were still unpaid at the close of business on August 31. Within 90 days the treasurer mails each owner of record a notice that the certificate issued and that failure to pay will transfer ownership of the property to the county no earlier than 2 years after issuance.
When taxes go delinquent
Real property taxes are payable in full by January 31 or in two equal installments due January 31 and July 31. Miss the first installment and the entire unpaid balance is delinquent as of February 1; miss the second and the entire unpaid balance is delinquent as of August 1. Interest then runs at 1 percent per month or fraction of a month from the preceding February 1, and any county board, or the common council of a city collecting its own taxes under s. 74.87, may by ordinance add a penalty of up to 0.5 percent per month on top. The combined statutory ceiling is 1.5 percent per month, which is 18 percent a year, and none of it is compounded. That money is retained by the county treasurer for the county. Anyone may clear the delinquency at any time before the tax certificate issues.
What happens after the sale
A statutory clock the county runs against itself, not an application by a certificate holder. On September 1 the county treasurer issues a tax certificate to the county on every parcel unpaid at the close of business on August 31, and within 90 days mails notice to each owner of record. Two years after issuance, if the parcel has not been redeemed, s. 74.57(2)(b) entitles the county to take a tax deed under s. 75.14, to foreclose the certificate by action as in a case of a mortgage under s. 75.19, or to foreclose the tax lien by action in rem under s. 75.521. Before a tax deed issues on the s. 75.14 route the county must serve written notice of application for tax deed on an owner of record, on an occupant where the parcel carries an occupied dwelling or business or agricultural building, and on at least one mortgagee of each unsatisfied recorded mortgage, then wait 3 months. The county board must also pass a resolution ordering issuance. Whichever route the county takes, title lands in the county in fee simple. The investor-facing event comes afterward, when the county sells land it now owns under ss. 75.35, 75.36 and 75.69. Two steps in this sequence look like investor sales and are not: the September 1 tax certificate issued to the county under s. 74.57, and a sale of tax certificate revenues under s. 74.635, which sells a payment stream and conveys no interest in any parcel.
Leftover parcels between sales
Wisconsin has no statewide over-the-counter program at a fixed statutory price, and nothing like a state-held certificate to assign. What it has instead is county inventory that stays for sale. Section 75.35(2)(am) lets the county board sell its tax-deeded lands in whatever manner and on whatever terms it sets, and s. 75.35(2)(d) lets it hire licensed real estate brokers on commission. Section 75.69(1) accepts a multiple listing service posting as the required advertisement, so a county parcel can simply sit on the open market until someone buys it. After a parcel has been advertised once and not sold, the county may sell it for any amount, subject to a further class 1 notice and to county board or committee approval where the price is below appraised value. The practical route is to ask the county treasurer or land committee for the current list of unsold county-owned parcels and make a written offer. Approval still runs through the board or its designated committee, so nothing closes across a counter on the day. Counties name the same event differently, so search for all of them: a tax deed land sale, a county-owned property sale, a surplus land sale, or a foreclosed property sale.
These dates are the statewide statutory schedule. The exact auction date, registration deadline, and platform are set county by county, so confirm them on the Wisconsin county pages before you plan a bid. For the mechanics of the sale itself, see how to buy in Wisconsin.
Verified Sep 10, 2026 against Wisconsin statutes.
Tax Sale Atlas publishes educational information about public tax sale processes. This is not legal, financial, or investment advice. Rules, dates, and fees change; confirm with the county office before you bid.