Union County, Ohio
Union County is a county in Ohio. Its county FIPS code is 39159. Use the boundary map and neighboring areas below to check the jurisdiction you need.
- Official code
- 39159
- Representative coordinates
- 40.295901, -83.367042
- County type
- County
- County seat or government
- Marysville
- Resident population, July 2025
- 73,446
- Land area
- 1,118.131 km²
- Water area
- 13.416 km²
- State
- Ohio
The representative point identifies this area. It is not a street address or a boundary survey.
Time zones in Union County
| Time zone | Local time and UTC offset | Next clock change |
|---|---|---|
| America/New_York | UTC-05:00 in January; UTC-04:00 in July. Enable JavaScript for the live clock. | Enable JavaScript for upcoming changes. |
Listed zones overlap the mapped area. A point lookup can distinguish sides of a boundary. Your device’s zone may differ.
Census ZIP areas
43007 · 43015 · 43016 · 43017 · 43029 · 43036 · 43040 · 43045 · 43060 · 43061 · 43064 · 43067 · 43077 · 43084 · 43302 · 43319 · 43340 · 43342 · 43344 · 43345 · 43358
These statistical areas overlap the boundary. They are not delivery assignments; confirm mailing details with USPS ZIP Code Lookup.
Official county information
Union County government website ↗ is the next stop for county offices, tax, voting, jury and records information. A geographic lookup cannot determine eligibility, tax liability or a court obligation.
Cities, towns and communities
These areas overlap the mapped boundary; an overlap does not mean that every address belongs to both.
Areas sharing the mapped boundary
These areas touch this mapped boundary.
Before using this answer on a form
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