U.S. ZIP Code Boundary Data

Pricing varies by license tier (Single User to Unlimited) and geography (National, Single State, or Custom ZIPs up to 65). Use our pricing calculator to get instant pricing for your specific needs. National licenses start in the low thousands, while single-state and custom ZIP options offer more affordable entry points for regional applications.

Yes! We offer four free sample datasets in all eight formats:

• 50 ZIP Diverse Sampler - Hand-picked ZIPs nationwide (urban, suburban, rural)
• 100 ZIP Stratified Sampler - Algorithmically distributed across the U.S.
• SF Bay Area - Multi-county regional sample (~300 ZIPs)
• Los Angeles Metro - High-density urban sample (~400 ZIPs)

Each sample includes all 8 formats (Shapefile, GeoJSON, SQL Server, PostGIS, MySQL, KML, WKT, CSV). Visit our Technical Specs page to download samples.

Every license seat receives the same eight-format export bundle plus the year's quarterly drops — nothing is paywalled by tier within the data itself.

What ships on day one:

• Boundary polygons in Shapefile (.shp + .shx + .dbf + .prj), GeoJSON (RFC 7946 feature collection), KML for Google Earth and ArcGIS Online overlay, WKT for raw geometry import, and three database-native flavors: SQL Server STGeomFromText scripts, PostGIS-ready WKT inserts, and MySQL spatial inserts with axis-order pragmas
• Centroid points in the same eight formats, including ZIPs that lack polygon coverage (PO Box, Unique-recipient, Military)
• 21 attribute columns per feature: ZIP, ZIPTYPE, primary city, state, county FIPS, MSA/CBSA codes, residential delivery count, business delivery count, total population, total housing units, area in square miles, and the RELVER vintage stamp
• Integration cookbook with sample SQL, sample Leaflet/Mapbox load, sample ArcGIS Python toolbox snippet
• Quarterly download notifications for the next four release cycles after purchase

Tier-specific extras: Department and Enterprise tiers include support-channel priority routing; Enterprise (50+ seats) additionally carries a named account manager and phone-channel access during business hours.

Geometries ship in EPSG:4326 (the WGS84 geographic CRS) with lon-lat axis order in every export format — Shapefile, GeoJSON, KML, WKT, and the SQL Server / PostGIS / MySQL flavors. That's the convention Leaflet, Mapbox GL, deck.gl, ArcGIS Online, and most modern map renderers expect, so polygons load without a manual reprojection.

Vertex coordinates carry 6–7 decimal places, well under polygon-edge precision. Distance and area calculations on raw lat-lon data return degrees, not meters — when accuracy matters, reproject into a UTM zone or state-plane CRS first.

Centroid files include all ZIP Codes (~33,000 records), including PO Box and Unique ZIP Codes that don't have street delivery areas. Boundary files only include polygonal ZIP Codes (~41,000 records) with geographic extent. Use boundaries for mapping and spatial analysis; use centroids for geocoding, distance calculations, and point-in-polygon queries.

Yes, some ZIP Codes serve areas in multiple states. These are represented as single polygons and assigned to the state used in their mailing address, not the state where their centroid falls. This ensures ZIP Codes align with USPS addressing conventions.

Filler ZIP Codes are synthetic ZIP Codes (###MH for water, ###MX for land) that ensure 100% continuous national coverage with no gaps or holes. They represent areas where USPS does not provide mail delivery-remote wilderness, large water bodies, national parks, military reservations.

These fillers eliminate map gaps and ensure clean topology for spatial analysis. They always have zero population and zero delivery counts. Filler ZIPs are clearly marked in the ZIPTYPE field as "FILLER" so you can filter them out if needed.

Quarterly release cadence — four shipments per license year, each one consolidating the prior three months of USPS carrier-route change-files (Pub 28 LACS, DPF, and DPV deltas) into rebuilt polygons.

Vintage stamps every record in the RELVER attribute (e.g., 202508 = the August 2025 release pulled from the August USPS publication cycle).

What rolls in between releases: net-new ZIP polygons for new construction or boundary realignment, retired ZIPs dropped, boundary edges re-walked where Census TIGER updates or USPS route restructures shifted them, and demographic counts re-aggregated against the latest population estimates.

Yes! Our data is compatible with all major GIS platforms:

• ArcGIS: Use Shapefile format (drag-and-drop) or import GeoJSON
• QGIS: Supports Shapefile and GeoJSON natively
• PostGIS: Import-ready SQL scripts included with proper SRID and geometry types
• SQL Server: Uses geography type with STGeomFromText()
• MySQL/MariaDB: Includes axis-order specification for correct coordinate handling

Visit our Technical Specs page for detailed import instructions and code examples for each platform.

Polygon edges follow a hybrid construction pipeline: USPS delivery-route assignments seed the topology, then edges snap to Census TIGER/Line street centerlines wherever a road forms the boundary. Urban polygons typically resolve to within 50–100 meters of the true delivery line; sparser road networks (rural counties, federal land, intermountain west) widen that bound proportionally because there are fewer reference vertices to snap against.

What the precision does and does not mean:

• Vertex storage is 6–7 decimal places, so the polygon geometry can be re-projected without losing any of the source resolution
• Point-in-polygon containment queries at ZIP granularity ("does this address fall in 90210?") are reliable across the dataset
• The boundaries are not parcel-level: they encode mail-delivery territory, not legal lot lines, easements, or tax-roll polygons
• Polygon area calculations on raw EPSG:4326 geometry return degrees-squared; a state-plane or UTM reprojection is required before computing real square miles or acres

Most overlay errors people report turn out to be coordinate-order issues (lat-lon vs lon-lat) at the consumer end, not source-data accuracy issues — the dataset is consistently lon-lat across every export format.

No! Our proprietary process includes filler ZIP Codes (###MH for water, ###MX for land) to ensure 100% continuous coverage of the United States. This eliminates map gaps in areas without USPS delivery service-like remote wilderness areas, large lakes, military reservations, and national parks. Filler ZIPs are clearly marked in the ZIPTYPE field so you can filter them if needed, but they ensure clean topology and edge-to-edge coverage for professional cartography.

Four scheduled releases per calendar year, one each quarter, with bonus interim shipments only if a USPS publication carries a high enough change-rate to warrant it (rare).

Every license carries 12 months of those quarterly drops included; you get email notifications with manifest deltas as each release publishes. The last shipment in your active window stays usable forever — license expiry stops new shipments, not the data you've already pulled.

Renewal is annual and only required if you want the next quarter's polygons and centroid updates.

Two delivery channels.

Email notifications go out every release with signed download URLs and the manifest (changed-ZIP list, vintage stamp, format checksums). Your account dashboard mirrors the same downloads for as long as the license is active — pull as many times as you like, switch formats between releases, re-download a prior quarter if needed.

License expiry just freezes the available downloads list at the last in-window release; the polygons, centroids, and attribute tables you've already retrieved stay perpetually licensed under the terms in effect at purchase.

Yes — ZIP polygons are operational mail-delivery zones, so they realign whenever the USPS reorganizes carrier routes. Three flavors of change show up:

• Edge nudges: small vertex shifts where a route handoff between two adjacent ZIPs moves a block-face from one polygon to its neighbor. Most quarterly drops contain dozens of these; individually they're under 100 m of edge movement.
• Topology events: ZIP splits (a single growing polygon partitions in two), ZIP merges (two adjacent polygons consolidate as a route is decommissioned), and full retirements (the polygon disappears because the carrier route was dissolved). These show up roughly once per quarter nationally.
• Attribute refresh: counts (residential, business, population, housing) re-aggregate against the latest delivery-statistics or population-estimate base, even when the polygon geometry is identical.

Each quarterly release ships the rebuilt geometry plus a changeset describing which ZIPs hit each of the three categories, so downstream pipelines can detect-and-diff rather than full-replace. Historical vintages (one year back per quarter as standard, deeper on request) are available if you need to back-test against a frozen baseline — the diff between any two quarters is recoverable from the RELVER-stamped data.