Wis. Stat. § 5.55: Information.

On every ballot, except a voting machine ballot, shall be printed “Official .... Ballot” or “Official .... Ballot for ....” followed by the designation of the polling place for which the ballot has been prepared, the date of the election, and the official endorsement and blank certificates. The number of the ward or wards or aldermanic district, if any, and the name of the municipality may be omitted in printing and stamped or written on the ballots at any location which is clearly visible at the option of the county clerk. Printed information and initials shall appear on the back and outside of the ballot.