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zipcodes.pro — STATE/OH/COUNTY/MERCER

Mercer County, OH ZIP codes

There are 10 ZIP codes in Mercer County, OH, in 10 towns, from 45310 to 45883. The largest are 45822 (Celina), 45828 (Coldwater) and 45846 (Fort Recovery).

The county seat is Celina.

ZIP codes
10
Towns
10
County seat
Celina
County FIPS
39107
State
Ohio
Population
42,484
Median household income
$76,782
Land area
462 sq mi
Metro area
Celina

Mercer County ZIP codes by town

Celina (county seat)
45822

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

Map of Mercer County ZIP codes

45310458224582645828458464586045862458664588245883

The ZIP codes of Mercer County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Mercer County in numbers

About 42,484 people live in Mercer County, in 16,408 households, the 57th most populous of Ohio's 88 counties. The median household income is $76,782 a year, 8% above the Ohio median of $71,389 (US: $80,734). The median owner-occupied home is valued at $210,600 (about the same as the Ohio median), and median gross rent is $804 a month. The median age is 39.4; 21.9% of adults 25 and over hold a bachelor's degree or higher (31.5% across Ohio); the average commute takes 19 minutes.

Population42,484Mercer42,484
Households16,408Mercer16,408
Median age39.4Mercer39.4Ohio39.7US 38.9
Median household income$76,782Mercer$76,782Ohio$71,389US $80,734
Median home value$210,600Mercer$210,600Ohio$214,800US $332,700
Median gross rent$804Mercer$804Ohio$1,034US $1,413
Bachelor's degree or higher21.9%Mercer21.9%Ohio31.5%US 35.7%
Mean commute18.5 minMercer18.5 minOhio23.4 minUS 26.4 min
Population density92 / sq miMercer92 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Mercer County

Largest towns in Mercer County
TownZIP codesPopulation
Celina 1 10,903
Coldwater 1 4,191
St. Henry 1 2,741
Fort Recovery 1 1,729
Maria Stein 1 1,305
Rockford 1 1,008
Mendon 1 713
Chickasaw 1 394
Burkettsville 1 227
Montezuma 1 117

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Mercer County.

Not sure you are in Mercer County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Mercer County, with figures

ZIP codes in Mercer County
ZIP City Type Population Median income Median home
45310 Burkettsville , OH Standard 227 $77,917 $207,000
45822 Celina , OH Standard 19,957 $70,200 $182,700
45826 Chickasaw , OH Standard 394 $101,250 $296,900
45828 Coldwater , OH Standard 6,404 $72,703 $252,100
45846 Fort Recovery , OH Standard 4,644 $91,736 $249,400
45860 Maria Stein , OH Standard 2,326 $111,269 $296,000
45862 Mendon , OH Standard 1,417 $45,556 $108,200
45866 Montezuma , OH Standard 117 $80,833 $110,900
45882 Rockford , OH Standard 2,919 $74,625 $161,700
45883 Saint Henry , OH Standard 4,144 $113,967 $297,000

Cite this page

zipcodes.pro. “Mercer County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/oh/county/mercer

Underlying data is public domain or openly licensed — sources, vintages and licences.