Allen County, Ohio
County seat: Lima · Population 100,881 (2025) · 403 sq mi
Allen County is the 26th most populous of Ohio's 88 counties, with 100,881 people (2025 estimate). Its county seat is Lima. The map shows its 9 cities and towns and the 5 neighboring counties.
Allen County facts
- County seat
- Lima
- Population (2025 estimate)
- 100,881 −1.3% since 2020
- Land area
- 403 sq mi 76th largest of 88
- Water area
- 4 sq mi
- Population density
- 251 per sq mi
- Established
- 1820
- Named after
- Ethan Allen American farmer, military officer and politician (1738–1789)
- Largest city
- Lima 34,695
- Median household income
- $64,038
- Cities and towns
- 9 plus 3 CDPs
- ZIP codes
- 20
- Time zone
- Eastern
- FIPS code
- 39003
Cities and towns in Allen County
Allen County has 9 incorporated cities, towns and villages. Populations count the people living inside Allen County; cities that cross a county line also list the other counties.
| Name | Type | Population 2025 | Also in |
|---|---|---|---|
| Lima (county seat) | City | 34,695 | |
| Delphos | City | 3,956 | Van Wert County |
| Bluffton | Village | 3,666 | Hancock County |
| Spencerville | Village | 2,165 | |
| Elida | Village | 1,904 | |
| Cairo | Village | 507 | |
| Harrod | Village | 426 | |
| Lafayette | Village | 401 | |
| Beaverdam | Village | 311 |
Unincorporated communities (CDPs)
Census-designated places are communities without their own city government; the county provides their services.
| Community | Population | Also in |
|---|---|---|
| Fort Shawnee | 6,209 | |
| Westminster | 526 | |
| Gomer | 148 |
ZIP codes in Allen County
20 ZIP codes reach into Allen County. ZIP codes ignore county lines, so some also cover a neighboring county.
- 45801
- 45804
- 45805
- 45806 also Auglaize County
- 45807
- 45808
- 45809
- 45810 also Hardin and Hancock counties
- 45812 also Hardin County
- 45817 also Hancock and Putnam counties
- 45820
- 45830 also Putnam County
- 45833 also Van Wert and Putnam counties
- 45844 also Putnam and Van Wert counties
- 45850 also Hardin and Auglaize counties
- 45854
- 45877 also Putnam and Hancock counties
- 45887 also Auglaize, Van Wert and Mercer counties
- 45895 also Auglaize and Logan counties
- 45896 also Auglaize and Hardin counties
Population of Allen County, 2020–2025
Allen County shrank by 1,323 people (−1.3%) between April 2020 and July 2025: 395 more deaths than births and a net loss of 947 people from migration.
| Year (July 1) | Population |
|---|---|
| 2020 | 102,116 |
| 2021 | 101,705 |
| 2022 | 100,974 |
| 2023 | 100,810 |
| 2024 | 100,952 |
| 2025 | 100,881 |
Neighboring counties
- Auglaize County southwest · 45,909 people
- Putnam County north · 34,380 people
- Van Wert County west · 29,013 people
- Hardin County east · 30,072 people
- Hancock County northeast · 75,034 people
Printable Allen County map
The PDF is a vector file with real text: it prints sharp on Letter paper and you can search it for a town. The PNG is 2400 pixels wide for slides and documents. Both are free to use with a credit to WhichCounty.
- PDF (Letter) (94 KB)
- PNG (2400 px) (61 KB)
Paste this code to embed the map on your site:
Sources
- Boundaries: U.S. Census Bureau, 2025 Cartographic Boundary Files (1:500,000).
- Population: Census Bureau county and city estimates, Vintage 2025. CDP populations: American Community Survey 2020–2024.
- Places and ZIP codes: Census Bureau 2026 Gazetteer and 2020 ZIP Code Tabulation Area relationship files.
- County seat, founding year and name origin: Wikidata (CC0), checked against state sources.
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