Wisconsin - Area of significance: Architecture
| Ripon College Historic District |
| Risum Round Barn |
| Ritger Wagonmaking and Blacksmith Shop |
| Riverbend |
| Riverside Cemetery |
| Riviera, The |
| Roberts House |
| Robertson, John A. and Martha, House |
| Robinson, Charles, House |
| Robinson Hill Historic District |
| Robinson, John C. and Mary, Farmstead |
| Rock Mill |
| Rockwood Lodge Barn and Pigsty |
| Roddis, Hamilton and Catherine, House |
| Roe, Ole K., House |
| Roethlisberger House |
| Rogers, Henry J,. and Cremora, House |
| Roosevelt Avenue Historic District |
| Roosevelt Elementary School |
| Roosevelt School |
| Roosevelt Terrace |
| Roosevelt, W. A., Company |
| Rountree Hall |
| Rountree, J. H., Mansion |
| Ruhland, Charles and Anna |
| Runkel, John P. and Mary, House |
| Rural on the Crystal Historic District |
| Sacred Heart Church |
| Saint Ann's Catholic Church and Cemetery |
| Saint Bernard's Chruch Complex |
| Saint George Melkite Catholic Church |
| Saint James Court Apartments |
| Saint John Evangelical Lutheran Church |
| Saint Luke's Church Complex |
| Saint Peter's Evangelical Lutheran Church |
| Saints Peter and Paul Roman Catholic Church Complex |
| Saint Vincent's Infant Asylum |
| Salem Evangelical Church |
| Salem Evangelical Church |
| Salsbury Row House |
| Sanger, Casper M., House |
| Sauk City Fire Station |
| Sauk City High School |
| Sauk County Courthouse |
| Saxonia House |
| Schauwitzer, Carl and Therese, House |
| Schendel, Reinhard and Amelia, House |
| Schlitz, Joseph, Brewing Company Saloon |
| Schlitz, Victor, House |
| Schoenicke Barn |
| Schofield, Robert, House |
| Schofield School |
| Schramka Funeral Home |
| Schroeder-Bohrod House |
| Schuetter, Henry House |
| Schuetz, E.K., House |
| Schulze, Ferdinand, House |
| Schumann, Frederick, Farmstead |
| Schunk, Jacob, Farmhouse |
| Schuster, George, House and Carriage Shed |
| Schuttler, Henry and Mary, House |
| Schwahn, William and Tilla, House |
| Schwartz, Bernard and Fern, House |
| Schwartz Family Home |
| Scott, T. B., Free Library |
| Second Church of Christ Scientist |
| Second Street Commercial District |
| Second Ward School |
| Security Bank |
| Security Savings Bank |
| Senn, John L., House |
| Sensenbrenner, J. Leslie, House |
| Seven Gables |
| Seven Pines Lodge |
| Seventh Day Baptist Church |
| Severance-Pipe Farmstead |
| Sevona Cabin |
| Sharrow, Frances Kurth, House |
| Shattuck, Franklyn C., House |
| Shaw Point Historic District |
| Shearer-Cristy House |
| Sheboygan County Courthouse |
| Sheboygan Municipal Auditorium and Armory |
| Sheboygan Post Office |
| Sheboygan Theater |
| Sheeley House |
| Shekey, Albert and Mary, House |
| Sheridan Apartment Building |
| Sherman Avenue Historic District |
| Sherman House |
| Sherry, Henry, House |
| Shoop Building |
| Shopiere Congregational Church |
| Shorecrest Hotel |
| Shorewood Historic District |
| Siegner, George V., House |
| Sign of the Willows |
| Silurian Mineral Springhouse |
| Simeon Mills Historic District |
| Simmons, Gilbert M., Memorial Library |
Data from United States Park Service and Wikidata
