Towns
| State | City/Town | Town Title |
|---|---|---|
| Iowa | Somers | Somers, IA |
| Iowa | South Amana | South Amana, IA |
| Iowa | South English | South English, IA |
| Iowa | Spencer | Spencer, IA |
| Iowa | Sperry | Sperry, IA |
| Iowa | Spillville | Spillville, IA |
| Iowa | Spirit Lake | Spirit Lake, IA |
| Iowa | Spragueville | Spragueville, IA |
| Iowa | Springbrook | Springbrook, IA |
| Iowa | Springville | Springville, IA |
| Iowa | Stacyville | Stacyville, IA |
| Iowa | Stanhope | Stanhope, IA |
| Iowa | Stanley | Stanley, IA |
| Iowa | Stanton | Stanton, IA |
| Iowa | Stanwood | Stanwood, IA |
| Iowa | State Center | State Center, IA |
| Iowa | Steamboat Rock | Steamboat Rock, IA |
| Iowa | Stockport | Stockport, IA |
| Iowa | Stockton | Stockton, IA |
| Iowa | Storm Lake | Storm Lake, IA |
| Iowa | Story City | Story City, IA |
| Iowa | Stout | Stout, IA |
| Iowa | Stratford | Stratford, IA |
| Iowa | Strawberry Point | Strawberry Point, IA |
| Iowa | Stuart | Stuart, IA |