Public ArcGIS MapServer endpoint for Hamilton County parcel data. URL, supported fields, and a working sample query, copy it, or open it directly in the UrbanKit parcel lookup tool.
https://cagisonline.hamilton-co.org/arcgis/rest/services/HCE/Cadastral/MapServer/0PARCELIDParcel IDAUDPCLIDAuditor Parcel IDOWNNM1Owner Name (Primary)OWNNM2Owner Name (Secondary)OWNAD1Owner Address Line 1OWNAD1AOwner Address Line 1Acurl -s 'https://cagisonline.hamilton-co.org/arcgis/rest/services/HCE/Cadastral/MapServer/0/query?where=UPPER(OWNNM1)+LIKE+UPPER('%25SMITH%25')&outFields=PARCELID,OWNNM1,OWNNM2,OWNAD1,AUDPCLID&returnGeometry=false&f=json&resultRecordCount=10'https://cagisonline.hamilton-co.org/arcgis/rest/services/HCE/Cadastral/MapServer/0/query?where=UPPER(OWNNM1)+LIKE+UPPER('%SMITH%')&outFields=PARCELID,OWNNM1,OWNNM2,OWNAD1,AUDPCLID&returnGeometry=false&f=json&resultRecordCount=10Open this URL in a browser tab to see the raw ArcGIS JSON response.
| Field name | Label | Searchable |
|---|---|---|
| PARCELID | Parcel ID | YES |
| AUDPCLID | Auditor Parcel ID | YES |
| OWNNM1 | Owner Name (Primary) | YES |
| OWNNM2 | Owner Name (Secondary) | YES |
| OWNAD1 | Owner Address Line 1 | YES |
| OWNAD1A | Owner Address Line 1A | YES |
| OWNAD2 | Owner Address Line 2 (City, State ZIP) | NO |
| TAXDST | Tax District | NO |
| LGLDS1 | Legal Description Line 1 | NO |
| LGLDS2 | Legal Description Line 2 | NO |
| BOOK | Deed Book | NO |
| PAGE | Deed Page | NO |
99 fields confirmed. This is the CAGIS (Cincinnati Area Geographic Information System) cadastral parcel polygon layer. Key fields include: PARCELID (12-digit parcel ID), AUDPCLID (auditor parcel ID), OWNNM1/OWNNM2 (owner names), OWNAD1/OWNAD1A/OWNAD2 (owner address), LGLDS1/LGLDS2/LGLDS3 (legal description), PREVOWN1/PREVOWN2 (previous owners), BOOK/PAGE (deed reference), TAXDST (tax district), MLTOWN (municipality), GRPPCLID (group parcel ID), PNTPCLID (point parcel ID), PROPTYID (property ID). Condo layers are separate (layers 5 and 6). Layer 2 (Hamilton County Parcel Attributes) joins assessment data. Layer 0 is the polygon geometry with ownership. Owner query confirmed: UPPER(OWNNM1) LIKE '%SMITH%' returns real parcels. Hamilton County, OH is the Cincinnati metropolitan area (FIPS 39061).
CAGIS (Cincinnati Area Geographic Information System), Hamilton County Auditor, https://www.hamilton-co.org/auditor/maps
Hamilton County's CAGIS.Ham_Parcel_Poly layer exposes parcel identifiers (Parcel ID, Auditor Parcel ID) and owner names (Owner Name (Primary), Owner Name (Secondary), Owner Address Line 1, Owner Address Line 1A). Use it for owner-name lookups and PIN-keyed record pulls. 6 of 12 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 Hamilton County actually publishes, not what you might expect from a national standard (there isn't one).
For background, see What is an APN?
cagisonline.hamilton-co.org serves Hamilton County, Ohio 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 Hamilton 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.
Hamilton County's layer is hosted by the county on cagisonline.hamilton-co.org. Public ArcGIS endpoints rarely rate-limit individual reads, but cagisonline.hamilton-co.org 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.