Identifiers: city · CDP
| Rank | Community | Population |
|---|---|---|
| 1 | Sioux City (city), IA | 85,797 |
| 2 | Le Mars (city), IA | 10,571 |
| 3 | Sergeant Bluff (city), IA | 5,015 |
| 4 | Moville (city), IA | 1,687 |
| 5 | Kingsley (city), IA | 1,396 |
| 6 | Sloan (city), IA | 1,042 |
| 7 | Lawton (city), IA | 943 |
| 8 | Hinton (city), IA | 935 |
| 9 | Correctionville (city), IA | 766 |
| 10 | Whiting (city), IA | 745 |
| 11 | Merrill (city), IA | 717 |
| 12 | Salix (city), IA | 295 |
| 13 | Bronson (city), IA | 294 |
| 14 | Hornick (city), IA | 255 |
| 15 | Climbing Hill (CDP), IA | 97 |