8 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 43040 | Marysville | 37,582 |
| 43344 | Richwood | 6,049 |
| 43358 | West Mansfield | 2,628 |
| 43045 | Milford Center | 1,665 |
| 43067 | Raymond | 1,655 |
| 43036 | Magnetic Springs | 326 |
| 43077 | Unionville Center | 278 |
| 43007 | Broadway | 34 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 8 ZCTAs in Union County, Ohio (US Census).