USA Geocoding Coverage

Address-level geocoding across all 50 US states with house-number precision, ZIP code support, county context, and secondary unit parsing.

What is covered

Map Zena supports geocoding across all US states and territories. Urban and suburban areas have strong address-point coverage, delivering precise results for house-number queries. Lower-density areas fall back to street-range interpolation, then city centroid. ZIP-only queries are also supported for regional and area-level use cases.

Address componentCoverage detail
House number + streetAddress-point data in urban/suburban areas; range interpolation elsewhere
Secondary unitsApt, Suite, Unit, Floor, Ste, # — parsed and matched where available in source records
City and place nameIncorporated cities, CDPs, and named places nationally
CountyReturned in all results where county attribution is available
StateAll 50 states plus DC; two-letter abbreviation and full name both accepted
ZIP codesZIP5 matching; ZIP+4 accepted and used for precision improvement where available
Rural routesBest-effort mapping to route geometry or nearest locality centroid

US address structure and normalization

Standard US postal addresses follow the format number street direction type, city state ZIP, for example 1600 Pennsylvania Ave NW, Washington, DC 20500. Common USPS street type abbreviations (St, Ave, Blvd, Dr, Ln, Ct, Pl, Rd) and directional prefixes and suffixes (N, S, E, W, NE, NW, SE, SW) are normalised before matching. Both abbreviated and full-form inputs produce consistent results.

Queries without a ZIP code still resolve correctly in most cases, but adding a ZIP5 or state code substantially reduces ambiguity for street names that exist in many cities — for example, Main Street appears in nearly every US state.

ZIP codes and county context

ZIP5 codes are matched to the correct city and state in the geocoding index. ZIP+4 codes, where included in the query, can improve position accuracy to the delivery-point level in dense urban areas. County name and FIPS-style admin codes are returned in the response where the address record includes county attribution, which is useful for regulatory, tax, or territory-assignment workflows.

Secondary unit parsing

Secondary designators — Apt, Suite, Unit, Floor, Ste, and the hash symbol (#) — are parsed from query strings and matched against sub-building records where available. For queries where the secondary unit cannot be matched, the result falls back to the parent building or street range.

Secondary unit formats accepted
123 Main St Apt 4B, Chicago, IL 60601
456 Market Street Suite 200, San Francisco, CA 94105
789 Oak Ave Unit 3, Austin, TX 78701
321 Pine St #12, Seattle, WA 98101

Example query patterns

GET /geocode?q=
1600 Pennsylvania Ave NW, Washington, DC 20500
1 Market St, San Francisco, CA 94105
Austin, TX 78701
Los Angeles County, CA
90210

Common use cases

  • E-commerce and retail — Validate shipping addresses at checkout and assign them to fulfillment zones or carrier service areas.
  • Lead enrichment and CRM — Geocode contact addresses to add county, DMA, or territory fields for sales routing.
  • Property technology — Geocode listing addresses for map pins, school-district overlays, and flood-zone queries.
  • Ride-share and on-demand delivery — Convert user-entered address strings to precise pickup and drop-off coordinates.
  • Tax and regulatory compliance — Return county and state for address records to apply the correct tax jurisdiction or regulatory rule set.

Reverse geocoding for US addresses

The reverse geocoding endpoint converts latitude/longitude coordinates to a nearest US address, including house number, street, city, county, state, and ZIP. This is commonly used in mobile apps, telematics platforms, and IoT fleet systems where a GPS position needs a human-readable label.

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