Indiana - Criteria: C (architecture/engineering)
| Shelbyville High School |
| Shelton |
| Sheridan Downtown Commercial Historic District |
| Sherman Building |
| Shields' Mill Covered Bridge |
| Shirk-Edwards House |
| Shirk, W. W., Building |
| Shortridge High School |
| Shortridge-Meridian Street Apartments Historic District |
| Shrewsbury, Charles L., House |
| Shull, Henry, Farmhouse Inn |
| Sid-Mar |
| Siegel's Department Store |
| Sigler, Eli, House |
| Silver Lake Historic District |
| Simonson, Alfred, House |
| Simpson-Breedlove House |
| Simpson Memorial United Methodist Church |
| Sim Smith Bridge |
| Skinner, DeForest, House |
| Smith Covered Bridge |
| Smith, Everel S., House |
| Smith Field |
| Smith, Henry W., House |
| Smith, John W., House |
| Smith, Robert, Mortuary |
| Smith, Samuel G., Farm |
| Snow Hill Covered Bridge |
| Soldiers and Sailors Memorial Coliseum |
| Solomon Enclave |
| Sommer, August, House |
| Sommerer House |
| Sons of Israel Synagogue |
| Souder, Dr. Christopher, House |
| South 9th Street Historic District |
| South Bend City Cemetery |
| South Bend Remedy Company |
| South Frankfort Historic District |
| South Grade School Building |
| Southmoor Apartment Hotel |
| Southport High School, Old |
| South Walnut Street Historic District |
| South Wayne Historic District |
| Southwood Park Historic District |
| Spencer County Courthouse |
| Spencer Public Library |
| Spencer Town Hall and Fire Station |
| Spencerville Covered Bridge |
| Spink |
| Spink Arms Hotel |
| Spring Street Freight House |
| SS CLIPPER |
| Stahly-Nissley-Kuhns Farm |
| Stallbohm Barn-Kaske House |
| Starke County Bridge No. 39 |
| Starke County Courthouse |
| Starr Historic District |
| State Bank of Hammond Building |
| State Bank of Indiana, Branch of (Memorial Hall) |
| State Normal Library |
| State Sanitorium Bridge |
| State Soldiers and Sailors Monument |
| State Street Commercial Historic District |
| State Street-Division Street Historic District |
| State Street Historic District |
| St. Augustine's Episcopal Church |
| St. Boniface Church |
| Steele Dunning Historic District |
| Stephenson Underwear Mill |
| Steuben County Courthouse |
| Steuben County Jail |
| Stevens, Levi, House |
| Stewart Manor (Charles B. Sommers House) |
| Stewart-Studebaker House |
| St. George Lutheran Church |
| Stidham United Methodist Church |
| Stinesville Commercial Historic District |
| St. James Memorial Chapel |
| St. John of the Cross Episcopal Church, Rectory and Cemetery |
| St. John's Church and Rectory |
| St. John's Episcopal Church |
| St. John's Evangelical Protestant Church |
| St. John's Lutheran Church |
| St. John's Lutheran Church and School |
| St. Joseph Catholic Church |
| St. Joseph County Infirmary |
| St. Joseph Neighborhood Historic District |
| St. Joseph School |
| St. Louis, Besancon, Historic District |
| St. Luke's Episcopal Church |
| St. Mary Historic District |
| St. Mary's Catholic Church |
| Stockheughter Covered Bridge |
| Stone Arch Bridge over McCormick's Creek |
| Stonebraker, John & Caroline, House |
| Stone, Gen. Asahel, Mansion |
| Stone, Judge Earl S., House |
| Stoner, Lycurgus, House |
| Stone's Trace |
| Stout, Daniel, House |
Data from United States Park Service and Wikidata
