Public ArcGIS MapServer endpoint for Fairfax County parcel data. URL, supported fields, and a working sample query, copy it, or open it directly in the UrbanKit parcel lookup tool.
https://www.fairfaxcounty.gov/mercator/rest/services/OpenData/OpenData_A9/MapServer/0PINParcel Identification NumberPARCEL_KEYParcel Key (numeric)curl -s 'https://www.fairfaxcounty.gov/mercator/rest/services/OpenData/OpenData_A9/MapServer/0/query?where=PIN+LIKE+%270304%25%27&outFields=PIN,PARCEL_TYPE&returnGeometry=false&f=json&resultRecordCount=10'
https://www.fairfaxcounty.gov/mercator/rest/services/OpenData/OpenData_A9/MapServer/0/query?where=PIN+LIKE+'0304%'&outFields=PIN,PARCEL_TYPE&returnGeometry=false&f=json&resultRecordCount=10Open this URL in a browser tab to see the raw ArcGIS JSON response.
| Field name | Label | Searchable |
|---|---|---|
| PIN | Parcel Identification Number | YES |
| PARCEL_KEY | Parcel Key (numeric) | YES |
| PARCEL_TYPE | Parcel Type (ORDINARY / CONDO) | NO |
| SRC_CONTROL | Source Control | NO |
Fairfax County (Northern Virginia, pop. 1.15 million) is the most populous jurisdiction in Virginia and covers 406 square miles, entirely distinct from Fairfax City -- a separate independent city (FIPS 51600) that sits geographically within the county but is governed and assessed independently. The county-direct parcel layer at fairfaxcounty.gov/mercator/rest/services/OpenData/OpenData_A9/MapServer/0 exposes PIN, PARCEL_KEY, PARCEL_TYPE (ORDINARY vs. CONDO), and SRC_CONTROL -- but no owner name. Fairfax keeps ownership data in a non-spatial table not exposed on this REST endpoint. For owner-name lookup, use the Fairfax County Real Estate Assessment Database at realestate.fairfaxcounty.gov; it supports search by address, parcel ID, and owner name. The GIS/Property MapServer at fairfaxcounty.gov/euclid/rest has 54 layers (parcels, tax districts, easements, flood zones, annotations) but also does not surface owner in the queryable parcel layer. PIN format is space-padded with section/block/lot grouping (e.g., '0304 39 0029'). Verified 2026-05-11: 369,267 polygon parcels. Updated daily from county cadastral.
Fairfax County GIS Division (Department of Information Technology), https://www.fairfaxcounty.gov/maps/
Fairfax County's Parcels layer exposes a parcel identifier (Parcel Identification Number). Use it for PIN-keyed record pulls (owner-name search lives on a separate assessor system). 2 of 4 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 2026-05-11.
/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 Fairfax County actually publishes, not what you might expect from a national standard (there isn't one).
For background, see What is an APN?
www.fairfaxcounty.gov serves Fairfax County, Virginia 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 Fairfax County's MapServer layer on 2026-05-11. 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.
Fairfax County's layer is hosted by the county on www.fairfaxcounty.gov. Public ArcGIS endpoints rarely rate-limit individual reads, but www.fairfaxcounty.gov 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.