Download US Counties Boundaries
Free download of every US county boundary — around 3,000 counties, parishes, boroughs, and independent cities covering all 50 states. Pick the format you need: GeoJSON, Shapefile, KML, GeoPackage, TopoJSON, or FlatGeobuf.
Boundary data provided by geoBoundaries (Runfola et al., 2020), licensed CC-BY 4.0. Please provide attribution when using this data.
About the US counties dataset
This page provides a one-click download of every US county, parish, borough, and independent city in every common geospatial format. Data comes from geoBoundaries — an open, peer-reviewed dataset maintained by the College of William & Mary and released under CC-BY 4.0.
Counties are the second-level subnational division (ADM2) in the United States. For coarser geometry use our US states boundaries page. For any other country, use the generic administrative boundaries downloader.
When to use which format
GeoJSON
The most flexible choice — works in QGIS, ArcGIS Pro, Mapbox, Leaflet, MapLibre, D3, and any web mapping library. Use the simplified version for client-side web maps.
Shapefile
Use for desktop GIS workflows in ArcGIS or QGIS, or when sharing with traditional GIS users. Delivered as a ZIP containing .shp / .dbf / .prj / .shx.
KML
Use for Google Earth, Google Maps, and Google My Maps. KML preserves the county names in feature popups by default.
TopoJSON
A topology-encoded extension of GeoJSON — significantly smaller for choropleths because adjacent counties share borders. Popular in D3.js dashboards.
GeoPackage
A modern, OGC-standard, single-file SQLite container. Ideal for portable GIS workflows where you want one file to carry the whole dataset.
FlatGeobuf
A binary streaming format optimised for fast load times in MapLibre, OpenLayers, or Leaflet. Use when minimum latency matters on a public-facing map.
Common uses for US county boundaries
- • County-level choropleths (election, demographics, public health, COVID, economic data)
- • Joining county-level Census, ACS, BLS, or BEA statistics to geometry
- • Sales-territory and market-area mapping at sub-state resolution
- • Insurance, real-estate, and risk modelling at county level
- • Spatial joins to assign a county and state to point data (customers, incidents, leads)
- • Reporting maps in Power BI, Tableau, Looker, or Observable
- • Service-area maps for utilities, telecom, or logistics
- • Boundary masks for satellite imagery or census-block analysis
Special cases in the US county dataset
- • Louisiana uses parishes instead of counties.
- • Alaska uses boroughs, plus census areas in regions that have no organised borough government.
- • Virginia has 38 independent cities that are administratively separate from the surrounding county.
- • District of Columbia is its own ADM1 and ADM2 equivalent.
Alternative US county boundary sources
The geoBoundaries data on this page is the easiest one-click option for most use cases. If you need higher-accuracy or FIPS-coded data:
- • US Census TIGER/Line — the authoritative federal source. Highest precision, includes FIPS, multiple vintages.
- • Natural Earth — cartographer-friendly generalised data for small-scale maps.
- • OpenStreetMap — community-edited boundaries from Overpass queries or Geofabrik extracts.
Frequently Asked Questions
How do I download US county boundaries as GeoJSON?
The boundaries for all US counties load automatically above. Click the GeoJSON download button to save the full-resolution file, or pick the simplified version for a smaller file optimised for web maps.
How many counties are included?
Roughly 3,000 — covering counties, parishes (Louisiana), boroughs and census areas (Alaska), and independent cities (Virginia). The dataset reflects the geoBoundaries ADM2 layer for the United States.
What formats can I download the counties in?
GeoJSON (full and simplified), Shapefile (ZIP), TopoJSON, KML, GeoPackage, and FlatGeobuf. GeoJSON, Shapefile, and TopoJSON download directly from geoBoundaries; KML, GeoPackage, and FlatGeobuf are converted in your browser using GDAL.
Where does this data come from?
From geoBoundaries (Runfola et al., 2020), an open peer-reviewed dataset of political administrative boundaries maintained by the College of William & Mary. Released under CC-BY 4.0 — free for commercial and non-commercial use with attribution.
How accurate are the county boundaries?
geoBoundaries county boundaries are derived from authoritative sources and are accurate enough for thematic mapping, choropleth visualisation, and most analytical work. For legal, cadastral, or regulatory applications use TIGER/Line from the US Census Bureau.
How large is the US counties GeoJSON file?
The full-resolution US counties GeoJSON is typically around 25–60 MB depending on vintage. The simplified version is a fraction of that size and is the right choice for web maps where exact precision is not needed.
Does the dataset include FIPS codes?
County feature properties from geoBoundaries include the county name and its ISO admin codes. FIPS codes are not always included by default — for FIPS-coded county boundaries the TIGER/Line dataset from the US Census Bureau is the authoritative source.
What is the difference between US counties and US states?
States are first-level (ADM1) divisions — there are 50 plus DC. Counties are second-level (ADM2) divisions — there are around 3,000. For state boundaries, see our US states page.