20 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 46530 | Granger | 31,907 |
| 46544 | Mishawaka | 31,138 |
| 46614 | South Bend | 29,339 |
| 46628 | South Bend | 27,929 |
| 46545 | Mishawaka | 26,581 |
| 46619 | South Bend | 21,179 |
| 46637 | South Bend | 16,079 |
| 46561 | Osceola | 14,499 |
| 46615 | South Bend | 14,411 |
| 46613 | South Bend | 11,726 |
| 46617 | South Bend | 10,402 |
| 46556 | Notre Dame | 8,159 |
| 46552 | New Carlisle | 6,665 |
| 46635 | South Bend | 6,552 |
| 46616 | South Bend | 6,219 |
| 46601 | South Bend | 4,933 |
| 46554 | North Liberty | 4,285 |
| 46536 | Lakeville | 3,086 |
| 46595 | Wyatt | 54 |
| 46624 | South Bend | 31 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 20 ZCTAs in St. Joseph County, Indiana (US Census).