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zipcodes.pro — STATE/KY/COUNTY/MERCER

Mercer County, KY ZIP codes

Mercer County, KY has 3 ZIP codes, in 3 towns: 40330, 40372 and 40310.

The county seat is Harrodsburg.

ZIP codes
3
Towns
3
County seat
Harrodsburg
County FIPS
21167
Population
23,028
Median household income
$64,824
Land area
249 sq mi
Area code
859

Mercer County ZIP codes by town

Harrodsburg (county seat)
40330

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

403104033040372

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 23,028 people live in Mercer County, in 9,181 households, the 51st most populous of Kentucky's 120 counties. The median household income is $64,824 a year, about the same as the Kentucky median of $63,726 (US: $80,734). The median owner-occupied home is valued at $202,300 (about the same as the Kentucky median), and median gross rent is $831 a month. The median age is 42.9; 24.9% of adults 25 and over hold a bachelor's degree or higher (27.6% across Kentucky); the average commute takes 27 minutes.

Population23,028Mercer23,028
Households9,181Mercer9,181
Median age42.9Mercer42.9Kentucky39.1US 38.9
Median household income$64,824Mercer$64,824Kentucky$63,726US $80,734
Median home value$202,300Mercer$202,300Kentucky$205,600US $332,700
Median gross rent$831Mercer$831Kentucky$967US $1,413
Bachelor's degree or higher24.9%Mercer24.9%Kentucky27.6%US 35.7%
Mean commute27.2 minMercer27.2 minKentucky24.0 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
Harrodsburg 1 9,313
Burgin 1 993
Salvisa 1 236

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
40310 Burgin , KY Standard 471 $56,477 $126,600
40330 Harrodsburg , KY Standard 21,250 $63,992 $199,500
40372 Salvisa , KY Standard 2,090 $74,205 $229,800

Cite this page

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

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