Miami County GIS Maps
Miami County, Ohio, has 108,774 residents and covers 406.5 square miles. The population grew 6.1% between the 2010 and 2020 census. More residents moved in than left over that decade. The FIPS code for Miami County is 39109.
Troy is the county's largest population center. Miami County also includes 11 zip codes, 12 public school districts and 34 municipalities. Those boundaries help explain why population, schools, and housing can look different from one part of the county to another. The map below shows how those county lines, zip codes, and school districts fit together, and the sections that follow use that same geography to show population, demographics, school enrollment and housing patterns in more detail.
Maps, GIS layers and sample data. Paid packages add full layers, analytics and database files.
Miami County Trends
- Population
- 108,774▴
- Median Home Value
- $209,200▴
- K-12 Enrollment
- 23,736▾
County analytics dashboards with historical trends & projections included in package downloads.
Free starter access previews county maps, lightweight GIS, and sample data. Paid packages unlock full GIS layers, analytics, and database files.
Miami County Maps
The maps below show a few of the county map styles included in our downloads. County packages include map exports in JPEG, PNG, SVG, PDF and GeoTIFF formats plus more than 20 GIS layers for mapping, research and analysis. Available layers include zip codes, area codes, subdivisions, school districts, political boundaries, roads, water features, points of interest and more.
County packages also include historical county demographics, business intelligence, analytical dashboards, AI-ready prompts, markdown files and related reference data. Everything is organized to save hours of manual work collecting current data, cleaning it and joining it together. That makes it easier to move faster on analytics, due diligence, business planning and location research. Paid packages are built for commercial use, but some package contents include source-specific attribution or notice guidance. Review Licensing & Data Source Notices.
Miami County Population
Miami County had 108,774 residents in 2020. That was 6.1% higher than in 2010. Miami County added 9,906 people between 2000 and 2020, which points to steady long-term growth. The county is fairly spread out, with about 268 people per square mile. Some of the county's most populated postal areas include Troy, Piqua and Tipp City.
Population Trend in Miami County OH
Miami County Population per 2000, 2010 and 2020 census counts with a baseline 2030 projection.
Miami County Zip Codes
Miami County has 11 zip codes. Some of the county's most populated zip codes include Troy (45373), Piqua (45356) and Tipp City (45371). Troy is the largest zip by population, with about 36,863 residents or 34% of the county total. Together, the three largest zips account for about 78% of all county residents based on 2020 population estimates.
Most Populated Zip Codes in Miami County OH
| ZIP | Area | Population | Trend |
|---|---|---|---|
| 45373 | Troy | 36,863 | ▴ 4.9% |
| 45356 | Piqua | 25,106 | ▾ -0.3% |
| 45371 | Tipp City | 23,205 | ▴ 26.6% |
| 45383 | West Milton | 6,885 | ▾ -2.2% |
| 45318 | Covington | 5,438 | ▴ 1.4% |
| Download all zip code data | |||
Miami County Zip Code populations and trends per most recent census data.
Miami County Demographics
Miami County has a median age of 41.1, which makes the county a little older than Ohio overall. About 23% of residents are under 18, while 19.1% are 65 or older. That gives the county a fairly even mix of younger families and older adults. The largest age group is 25 to 44 at about 30.3% of the population, which points to a solid working-age base. About 24.9% of adults have a bachelor's degree or higher, above the statewide figure of 30.9%. The county is mostly White by population, though Hispanic, Asian, Black and multiracial residents are also part of the local mix.
Key Demographics for Miami County OH
Median Age
41.1
Under 18
23%
Age 65+
19.1%
Bachelor's+
24.9%
Miami County School Districts
Miami County is served by 12 public school districts with 23,736 students enrolled in 2024. The largest districts on the county map are Northmont City, Troy City and Piqua City. Those three districts account for about 49% of public school enrollment in the map area. Total enrollment has stayed fairly steady in recent years, but it is slightly lower than it was in 2017.
Largest School Districts by Enrollment in Miami County OH
| District | Enrollment | Share | Trend |
|---|---|---|---|
| Northmont City School District | 4,676 | 19.7% | ▴ 0.2% |
| Troy City School District | 3,929 | 16.6% | ▾ -3.2% |
| Piqua City School District | 3,069 | 12.9% | ▾ -1.4% |
| Tecumseh Local School District | 2,555 | 10.8% | ▾ -1.6% |
| Tipp City Exempted Village School District | 2,323 | 9.8% | ▾ -0.8% |
| Download all school district data | |||
Miami County school district enrollment and trends per most recent NCES reporting data.
Miami County Housing & Real Estate
Miami County has a median home value of $209,200 and a median gross rent of $942. About 73% of occupied homes in the county are owner-occupied, so the local housing market leans heavily toward ownership. Home values run above the Ohio median, while rents come in below the state average. In March 2026, the median listing price was $337,098 and homes spent about 51 days on the market.
Miami County Housing Mix
Miami County housing mix: owner, renter and vacant units.
Miami County Housing Trends
Miami County median home value and rent trend (last 5 years).
Businesses in Miami County, OH
Miami County has 4,361 business listings across 631 categories. The largest categories in Miami County business listings are Churches & Religious Organizations (153, 3.5%), Auto Repair (91, 2.1%), and Medical Offices (89, 2.0%). The full Miami County business listings dataset includes names, categories, addresses and contact details where available. Miami County packages also include U.S. Census County Business Patterns data with establishment counts, employment and payroll by industry sector.
Top Business Categories in Miami County, OH
| Category | Businesses | Share |
|---|---|---|
| Churches & Religious Organizations | 153 | 3.5% |
| Auto Repair | 91 | 2.1% |
| Medical Offices | 89 | 2.0% |
| Contractors | 78 | 1.8% |
| Parks & Recreation | 73 | 1.7% |
| Real Estate Agents | 61 | 1.4% |
| Community & Nonprofits | 53 | 1.2% |
| Beauty Salons | 51 | 1.2% |
| Hair Salons | 50 | 1.1% |
| Pizza Restaurants | 48 | 1.1% |
Miami County Business Listings
| Business | Category | City |
|---|---|---|
| BrightView | Abuse And Addiction Treatment | Piqua |
| Towne Park | Accommodation | Troy |
| On Point Accounting and Tax | Accountant | Piqua |
| City of Troy Recreation Department | Active Life | Troy |
| Community Acupuncture for Pete's Sake | Acupuncture | Tipp City |
| Adam & Eve Stores | Adult Entertainment | Piqua |
| Bash Foo | Advertising Agency | Tipp City |
| Apple Farm Service Inc. | Agricultural Service | Covington |
| Seeds and Scraps | Agriculture | New Carlisle |
| Hartzell Propeller LLC | Aircraft Manufacturer | Piqua |
| Download Miami County business listings | ||
Miami County business listings sourced from Overture Maps. Includes locations with a high level of confidence.
Miami County Basemaps
Miami County map and data packages include a set of useful basemaps to help you get started quickly. These include a custom light grey canvas, USGS topo, imagery and other reference layers that make it easier to build clear, meaningful county maps using the included GIS layers, your own data or both. Pre-rendered map tiles for the light grey basemap are included so you can use them offline or host them on your own CDN.
Get the Full Miami County Data Package
This page shows a preview of what's included in the Miami County data package. The full package gives you a ready-to-use county data system with GIS layers, historical data, maps, database files and planning tools that save hours of manual data gathering, cleanup and joins. Everything is organized to help you skip data wrangling and start analysis faster.
- 20+ GIS layers for zip codes, school districts, roads, water, boundaries and more
- Historical county demographics, housing, income and trend data
- ZIP code population files and school district enrollment history
- Database files, markdowns, AI-ready prompts and documentation
- Map exports in PNG, JPEG, PDF, SVG and GeoTIFF formats
- Offline-ready data explorer, map and analytics tools
Paid packages support commercial use, client work, and derived outputs. Some package contents may include source-specific attribution or provider notices. See Licensing & Data Source Notices.
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Preview a Live Package Demo
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Nearby Counties
Browse county data pages for the counties that border Miami County. These nearby pages include the same mix of county maps, demographic summaries, school district context, housing trends and package links.