Public ArcGIS MapServer endpoint for Contra Costa County parcel data. URL, supported fields, and a working sample query, copy it, or open it directly in the UrbanKit parcel lookup tool.
https://gis.cccounty.us/arcgis/rest/services/CCMAP/Assessment_Parcels_ArcPro/MapServer/0APNAssessor Parcel NumberN_STR_NMSitus Street NameN_CTY_STSitus City/Statecurl -s 'https://gis.cccounty.us/arcgis/rest/services/CCMAP/Assessment_Parcels_ArcPro/MapServer/0/query?where=N_CTY_ST+LIKE+'CONCORD%25'&outFields=APN,N_STR_NM,N_STR_NBR,N_CTY_ST,LAND_VALUE,IMP_VAL,ACREAGE&returnGeometry=false&f=json&resultRecordCount=10'
https://gis.cccounty.us/arcgis/rest/services/CCMAP/Assessment_Parcels_ArcPro/MapServer/0/query?where=N_CTY_ST+LIKE+'CONCORD%'&outFields=APN,N_STR_NM,N_STR_NBR,N_CTY_ST,LAND_VALUE,IMP_VAL,ACREAGE&returnGeometry=false&f=json&resultRecordCount=10Open this URL in a browser tab to see the raw ArcGIS JSON response.
| Field name | Label | Searchable |
|---|---|---|
| APN | Assessor Parcel Number | YES |
| N_STR_NM | Situs Street Name | YES |
| N_STR_NBR | Situs Street Number | NO |
| N_CTY_ST | Situs City/State | YES |
| N_ZIP | Situs ZIP | NO |
| LAND_VALUE | Land Value | NO |
| IMP_VAL | Improvement Value | NO |
| TRA | Tax Rate Area | NO |
| USE_CODE | Use Code | NO |
| ACREAGE | Acreage | NO |
42 fields confirmed including APN, APN_CHECK, TRA, N_STR_NM, N_STR_SUF, N_ODD_EVN, N_STR_NBR, N_FRAC, N_APT_NBR, N_CTY_ST, N_ZIP, N_ZIP_EXT, DESC_, VIEW_, ACREAGE, C_DED_NBR, C_DED_DT, USE_CODE, LAND_VALUE, IMP_VAL, PER_PRPTY, TOT_AREA, XMP_CODE1, XMP_AMT1. Live query confirmed: N_CTY_ST LIKE 'CONCORD%' returns real Concord CA parcels (APN='510052007', LAND_VALUE=512317). NOTE: Owner name is NOT on this public layer per CA Gov Code 7928.205. The CCMAP Assessment Parcels service is the county-maintained assessor parcel layer for Contra Costa County (Concord, Richmond, Walnut Creek, Antioch, etc.). Hosted on the county's GIS server (gis.cccounty.us). The main CCMAP MapServer (/CCMAP/CCMAP) has no external query layer. maxRecordCount=2000. Capabilities: Map, Query, Data.
Contra Costa County GIS / CCMAP, DOIT GIS Division, https://contra-costa-gis-cocogis.hub.arcgis.com/
Contra Costa County's Assessment Parcels layer exposes a parcel identifier (Assessor Parcel Number) and address fields (Situs Street Name, Situs City/State). Use it for address-to-PIN lookups and identifier queries. 3 of 10 listed fields accept queries; the rest are returned on read but not indexed for search. Served as an ArcGIS MapServer layer, which supports query operations but not write operations; last verified 2026-05-15.
/query?where=…&outFields=*&f=jsonto the URL. The sample query above is a working example you can paste into a browser tab to see the raw JSON response.Counties publish parcel data through their own ArcGIS Server installations, each with its own schema. One county uses APN, another uses PIN, a third uses PARCEL_ID. Some expose owner names; others keep them on a separate assessor's portal. The searchable fields list above reflects what Contra Costa County actually publishes, not what you might expect from a national standard (there isn't one).
For background, see What is an APN?
gis.cccounty.us serves Contra Costa County, California parcels over public ArcGIS REST, but, like most county servers, it may not send the CORS headers a browser needs for a cross-origin fetch. If a direct browser call fails, the layer still works from curl, Postman, or a server-side script; the UrbanKit parcel lookup tool proxies the request, so a search that succeeds there confirms the layer is genuinely public.
We last verified Contra Costa County's MapServer layer on 2026-05-15. County GIS teams move services without notice, so if you hit a fresh 404, tell us and we'll re-check. Atlas entries are re-verified on a rolling basis.
Contra Costa County's layer is hosted by the county on gis.cccounty.us. Public ArcGIS endpoints rarely rate-limit individual reads, but gis.cccounty.us can throttle heavy automated traffic at the host level. Page through results with resultOffset / resultRecordCount and request only the fields you need. There's no API key and no charge from the county.