Wis. Stat. § 74.51: Discharge of delinquent taxes.

(1) Payment to discharge delinquency. Any person may, at any time before issuance of a tax certificate under s. 74.57, discharge delinquent real property taxes, special assessments, special charges or special taxes on real property by paying the delinquent amounts, together with interest and any penalty provided under s. 74.47 (2).

(2) Receipts for taxes paid. After a payment is made under sub. (1), the treasurer shall execute duplicate receipts showing the name of the person making the payment, the date of the payment, the description of the property upon which the payment was made and the amount paid. One copy of the receipt shall be delivered to the person making the payment and the other copy filed in the treasurer’s office.