Clark
Source:
Ohio
Clark is a county in Ohio with 15 ZIP codes and a total population of 138,293. All data is sourced from the U.S. Census Bureau American Community Survey (ACS) 2023 5-Year Estimates.
Clark is a county inside Ohio (FIPS code 39023) that contains 15 USPS ZIP codes covering a combined population of 138,293 according to Census ACS 5-Year Estimates. Counties are the natural bridge between state-level summaries and ZIP-level detail — crime statistics, HUD Fair Market Rents, and childcare pricing are all published at the county level, while household income and housing values are published at the ZIP level. This page reconciles the two views so you can see which ZIPs drive the county totals.
The 15 ZIPs listed below are ordered by population and each links to the full ZIP detail page with Census demographics, housing, income, home-price history, and cross-agency inputs. The most populated ZIP in Clark is 45503 covering Springfield with 32,999 residents at 734 people per square mile. Population density across ZIPs in this county varies — use the density column to spot urban cores versus rural delivery areas. A single county can contain both a dense downtown ZIP and a large rural ZIP covering several hundred square miles.
Because Clark uses FIPS code 39023, it joins cleanly to county-level federal datasets: HUD Fair Market Rent tables, FBI Uniform Crime Report data, and the Department of Labor National Database of Childcare Prices all key off the same code. That is how neighborhood scorecards combine ZIP-level Census demographics with county-level safety and affordability metrics. All data on this page comes from U.S. Census Bureau ACS 2023 5-Year Estimates and USPS ZIP Code Tabulation Area files — no estimates, no proprietary sources, no editorial scoring.
15
Total ZIPs
138,293
Total Population
ZIP Codes in Clark
Side-by-side: Compare 45503 vs 45505 →
| ZIP Code | City | Population | Density |
|---|---|---|---|
| 45503 | Springfield | 32,999 | 734 |
| 45505 | Springfield | 20,197 | 580 |
| 45504 | Springfield | 18,465 | 307 |
| 45344 | New Carlisle | 16,955 | 99 |
| 45502 | Springfield | 16,110 | 54 |
| 45506 | Springfield | 14,055 | 439 |
| 45323 | Enon | 5,019 | 306 |
| 45368 | South Charleston | 4,727 | 23 |
| 45341 | Medway | 3,883 | 260 |
| 45369 | South Vienna | 3,545 | 31 |
| 43153 | South Solon | 971 | 7 |
| 45349 | North Hampton | 427 | 718 |
| 45372 | Tremont City | 375 | 654 |
| 45319 | Donnelsville | 293 | 316 |
| 43010 | Catawba | 272 | 455 |
Official Data Resources
What are common questions about ZIP codes in this county?
What is the population of Clark?▼
What ZIP codes are in Clark?▼
What is the median household income in Clark?▼
Source: U.S. Census Bureau, American Community Survey (ACS) 5-Year Estimates (2023). Verify with Census Bureau →
Source: HUD USPS Crosswalk (ZIP-to-county mapping). Verify with HUD →
PlainZIP is not affiliated with the U.S. Census Bureau or any government agency.
Read our methodology — how this data is sourced, computed, and verified.