100 Smallest ZIP Codes in the United States by Population in O'Brien County, Iowa
Explore the 100 smallest ZIP codes in the United States ranked by population using U.S. Census demographic data. This page lists ZIP codes located in O'Brien County, Iowa.
| Rank | ZIP Code | City | State | Population |
|---|---|---|---|---|
| 1 | 51009 | CALUMET | IA | 166 |
| 2 | 51231 | ARCHER | IA | 621 |
| 3 | 51058 | SUTHERLAND | IA | 982 |
| 4 | 51245 | PRIMGHAR | IA | 1,096 |
| 5 | 51046 | PAULLINA | IA | 1,432 |
| 6 | 51248 | SANBORN | IA | 1,712 |
| 7 | 51346 | HARTLEY | IA | 2,201 |
| 8 | 51201 | SHELDON | IA | 6,278 |