There are 43 zip codes in St. Louis County, Missouri. The most populated is 63021, located in Ballwin. * 2024 populations estimated based on the latest ACS 5-year data.
Zip Code | Population | City |
|---|---|---|
| 63021 | 55,944 | Ballwin |
| 63129 | 51,893 | Saint Louis |
| 63031 | 50,568 | Florissant |
| 63123 | 50,347 | Saint Louis |
| 63017 | 42,686 | Chesterfield |
| 63136 | 42,385 | Saint Louis |
| 63122 | 41,416 | Saint Louis |
| 63033 | 41,037 | Florissant |
| 63011 | 36,515 | Ballwin |
| 63119 | 34,732 | Saint Louis |
| 63114 | 34,341 | Saint Louis |
| 63125 | 32,750 | Saint Louis |
| 63146 | 31,348 | Saint Louis |
| 63128 | 30,168 | Saint Louis |
| 63130 | 28,978 | Saint Louis |
| 63121 | 24,126 | Saint Louis |
| 63043 | 22,123 | Maryland Heights |
| 63141 | 20,781 | Saint Louis |
| 63137 | 20,390 | Saint Louis |
| 63135 | 19,764 | Saint Louis |
| 63005 | 19,734 | Chesterfield |
| 63034 | 19,031 | Florissant |
| 63105 | 19,003 | Saint Louis |
| 63138 | 18,602 | Saint Louis |
| 63131 | 18,531 | Saint Louis |
| 63042 | 18,143 | Hazelwood |
| 63025 | 17,708 | Eureka |
| 63074 | 15,888 | Saint Ann |
| 63126 | 15,201 | Saint Louis |
| 63134 | 14,023 | Saint Louis |
| 63132 | 13,995 | Saint Louis |
| 63124 | 10,997 | Saint Louis |
| 63044 | 10,821 | Bridgeton |
| 63117 | 9,691 | Saint Louis |
| 63143 | 9,097 | Saint Louis |
| 63144 | 9,027 | Saint Louis |
| 63040 | 8,662 | Wildwood |
| 63088 | 8,473 | Valley Park |
| 63038 | 7,153 | Wildwood |
| 63133 | 6,763 | Saint Louis |
| 63127 | 5,235 | Saint Louis |
| 63140 | 291 | Saint Louis |
| 63045 | 0 | Earth City |