About CountyGISMaps

CountyGISMaps provides GIS data, demographics, analytics and reference maps for every county in the United States. Every package is built from authoritative government sources, organized for immediate use, and licensed for commercial delivery.

The Problem We Solve

County-level GIS data is public. Finding it, cleaning it, joining it and getting it into a usable format is not. A single county project can pull from a dozen government portals — Census TIGER files, American Community Survey tables, NOAA climate archives, FBI crime statistics, election data — each with its own format, update cycle and edge cases.

We compile, clean, join and export that data so you can skip straight to the work.

What's in the Data

Each county package includes GIS boundary layers, multiple decades of demographic and economic data, housing market metrics, climate records, crime history and election results. Data ships in the formats your team actually uses.

GIS boundary layers

ZIP codes, tracts, roads, water, school districts, congressional districts, MSAs and more

Demographics back to 2009

Age, sex, race, education, income, employment and housing — annual ACS data

Population back to the 1800s

Decennial census records for most counties; some colonial-era estimates date to the 1600s

Housing data

Median home values, gross rent, owner vs. renter occupancy, housing unit counts and structure types from ACS

Climate records since 1970

Monthly and annual temperature, precipitation, heating and cooling degree days from NOAA

Crime data back to 1970

Violent and property crime by category from FBI UCR and the Marshall Project

Presidential election results

County-level vote totals and percentages across historical election cycles

Business listings & patterns by industry

Over 15 million business listings plus establishments, employment and payroll by NAICS code, 1998 forward

Every package exports to Shapefile, GeoJSON, GeoPackage, KML, GeoTIFF, CSV and Parquet. Reference maps ship as PNG, PDF and SVG.

Database-ready exports are included with paid packages. County and State packages include PostgreSQL and SQLite. The National Enterprise package adds MySQL, SQL Server, Oracle and Parquet with loader scripts for each platform.

Data Sources

All data comes from authoritative public sources. No crowd-sourced estimates, no synthetic fills. Each package includes documentation identifying the source, vintage and any attribution requirements for every dataset.

Source	Data	Coverage
U.S. Census Bureau	TIGER/Line boundaries, American Community Survey, Decennial Census, County Business Patterns	ACS 2009–present · Decennial 1790–2020
NOAA	Monthly and annual climate — temperature, precipitation, heating and cooling degree days	1970–present
FBI / Marshall Project	Uniform Crime Reports — violent and property crime by category	1970–2020
MIT Election Data Lab	County-level presidential election results	Historical election cycles
NANPA	Telephone area code boundaries	Current

Who Uses It

CountyGISMaps is built for anyone who works with county-level data professionally and needs to skip the sourcing phase.

Who	Real-world use cases	What they skip
GIS analysts & cartographers	Client deliverables, base layer prep, custom thematic maps, print atlases	Downloading raw TIGER files, reprojecting, clipping, and manually joining attribute tables
Urban & regional planners	Land use analysis, demographic projections, infrastructure studies, grant applications	Cross-referencing ACS tables with boundary files and building consistent multi-county datasets from scratch
Real estate researchers & platforms	Market analysis, neighborhood scoring, investor reports, site selection models	Pulling ACS housing tables, aligning them to county boundaries, and cross-referencing occupancy, value and rent data across multiple survey years
Market researchers & consultants	Trade area analysis, consumer profiling, site selection, competitive landscape reports	Pulling business patterns by NAICS, aligning them to geographies, and normalizing across counties
Data journalists & editorial teams	Election maps, housing affordability stories, demographic trend pieces, COVID-era analyses	Hunting for county-level election results and pairing them with Census demographics on deadline
Government contractors & policy teams	Grant writing, demographic impact assessments, redistricting support, NEPA filings	FIPS code lookups, Census API pagination, and stitching boundary data to socioeconomic tables
App developers & product builders	Location-aware apps, demographic APIs, real estate tools, embedded maps	Building ETL pipelines, normalizing geometry formats, and setting up spatial databases from raw government sources
Academic & institutional researchers	Longitudinal demographic studies, economic geography, public health analysis, climate research	Assembling consistent multi-decade county panels — population, income, climate, and crime — from scattered archival sources

Built for AI and Agentic Workflows

Every paid package includes assets prepared specifically for LLM consumption — not as an afterthought, but as a first-class deliverable. The data is structured, documented and pre-contextualized so it drops cleanly into a prompt, a RAG pipeline or an agent tool call without preprocessing.

What ships in every package

File	What it is	How it gets used
COUNTY_SUMMARY.md	A single Markdown file covering population, demographics, economy, housing, climate and geography for the county	Drop directly into a system prompt or user message as county context. Sized to fit comfortably in a context window.
DATA_CONTEXT.md	Schema reference written for LLM consumption — table names, field descriptions, data types, vintages and join keys	Feed to an agent or coding assistant so it can write accurate SQL, Python or R against the included data files without hallucinating column names.
PROMPTS.md	A library of county-specific prompts pre-written for ChatGPT, Claude and similar tools	Ready-to-run starting points for demographic analysis, economic summaries, site selection reasoning, comparison tasks and more.
SQL dumps + CSVs	Normalized relational data joined on FIPS codes, consistent field names across all 3,143 counties	Load into a local database and point an agent at it. Consistent schema means a query written for one county works for all of them.

What this enables

The consistent structure across counties is the key detail. A prompt, agent or pipeline built against one county's data works against any other county's data without modification. That makes multi-county comparison loops, state-wide analysis agents and national-scale RAG pipelines practical to build rather than painful.

Ask Claude or ChatGPT to summarize and compare two counties using COUNTY_SUMMARY.md files as context — no preprocessing required
Give a coding agent DATA_CONTEXT.md and a question; it writes the SQL query against the included database files without needing to infer the schema
Build a RAG pipeline over all counties in a state using the structured CSVs as a document store — FIPS codes give you a clean join key across every table
Run agentic loops that pull demographic, housing and economic context county-by-county using the same prompt template repeated across consistent data files
Feed PROMPTS.md to a team that doesn't know the data — the prompts are written to produce useful output without the user understanding the underlying schema

Licensing

Paid packages are licensed for commercial projects, derivative works and client delivery. Each package includes a LICENSE.txt, PROVIDER_NOTICES.txt and DATA_GUIDE.md that spell out use rights and any source-specific attribution requirements.

Full licensing terms are available at Licensing & Data Source Notices.