Public ArcGIS MapServer endpoint for St. Louis city parcel data. URL, supported fields, and a working sample query, copy it, or open it directly in the UrbanKit parcel lookup tool.
This page is the endpoint reference. If you came here to find a specific property, the St. Louis city parcel search runs this same layer in your browser, no account and no API key.
Search St. Louis city parcelsHave a street address but not the parcel number? Find the parcel number by address.
https://maps8.stlouis-mo.gov/arcgis/rest/services/ASSESSOR/Assessor_Public_Parcels/MapServer/11Field by field, whether any endpoint we index for St. Louis city answers it, and the evidence for each. We only call a field restricted when there is a stated reason we can cite. Everything else here is a fact about the services we index, not a claim about the law.
| Field | Status | Basis |
|---|---|---|
| APN | Answered | Documented in a field list on an endpoint we index. Not every row is populated. |
| Owner name | Answered | Documented in a field list on an endpoint we index. Not every row is populated. |
| Owner mailing address | Answered | Documented in a field list on an endpoint we index. Not every row is populated. |
| Site address | Answered | Documented in a field list on an endpoint we index. Not every row is populated. |
| Geometry | Answered | Documented in a field list on an endpoint we index. Not every row is populated. |
| Land use | Not published | No endpoint we index for this county documents this field, so a query cannot ask for it. That is a fact about the services we index, not a legal restriction, and not a statement that the county holds no such record. Where to request it. |
| Zoning | Not published | No endpoint we index for this county documents this field, so a query cannot ask for it. That is a fact about the services we index, not a legal restriction, and not a statement that the county holds no such record. Where to request it. |
OwnerNameOwner NameParcelIdParcel IDSITEADDRSite AddressOwnerAddrOwner Mailing Addresscurl -s 'https://maps8.stlouis-mo.gov/arcgis/rest/services/ASSESSOR/Assessor_Public_Parcels/MapServer/11/query?where=UPPER(OwnerName)%20LIKE%20%27SMITH%25%27&outFields=ParcelId,OwnerName,OwnerAddr,OwnerCity,SITEADDR&returnGeometry=false&resultRecordCount=10&f=json'
https://maps8.stlouis-mo.gov/arcgis/rest/services/ASSESSOR/Assessor_Public_Parcels/MapServer/11/query?where=UPPER(OwnerName) LIKE 'SMITH%'&outFields=ParcelId,OwnerName,OwnerAddr,OwnerCity,SITEADDR&returnGeometry=false&resultRecordCount=10&f=jsonOpen this URL in a browser tab to see the raw ArcGIS JSON response.
| Field name | Label | Searchable |
|---|---|---|
| OwnerName | Owner Name | YES |
| OwnerName2 | Owner Name 2 | NO |
| ParcelId | Parcel ID | YES |
| SITEADDR | Site Address | YES |
| OwnerAddr | Owner Mailing Address | YES |
| OwnerCity | Owner Mailing City | NO |
| OwnerState | Owner Mailing State | NO |
| OwnerZIP | Owner Mailing ZIP | NO |
| ZIP | Site ZIP | NO |
City of St. Louis, Missouri (FIPS 29510) is an independent city that belongs to no county, and it is NOT St. Louis County (29189, a separate record in this file on a different server). The Assessor's public parcels layer is ASSESSOR/Assessor_Public_Parcels/MapServer layer 11 (Parcels) on ArcGIS Server 11.2, listed on the city's data page. SERVER-SIDE ONLY: the server sends Access-Control-Allow-Origin only to its own origin (www.stlouis-mo.gov); for any other Origin a GET and its preflight return only Vary: Origin and Access-Control-Allow-Private-Network: true, so a browser on another site cannot read it and corsEnabled is false. Query it from a server, the metered API or the MCP, not from page script. The owner is OwnerName (max 40 characters, so long names are truncated at the source) with OwnerName2; the mailing address is OwnerAddr plus OwnerCity (max 13 characters, can read ST LOUIS MO) with OwnerState, OwnerZIP and OwnerCountry; the parcel id is ParcelId (11 digits, LowerParcelId also exists). SITEADDR carries runs of internal spaces (2233 PARK AV) and trailing padding, so a LIKE on a full street string misses; search on the house number plus a street word, or collapse whitespace on the client. Search with UPPER(OwnerName) LIKE 'SMITH%'; broad searches return exceededTransferLimit true at the 2000-row page. The layer has 194 fields and this record lists a subset. Layer 11 includes condominium master parcels, and the sub-accounts are layer 10 (not examined). No license or terms text is published on the data page. Verified live 2026-10-03: owner SMITH returned rows (first SMITH, DAVID E & SANDRA L TRS, parcel 22669130000, 2233 PARK AVE).
City of St. Louis Assessor's Office, https://www.stlouis-mo.gov/data/parcels.cfm
St. Louis city's Parcels layer exposes a parcel identifier (Parcel ID), owner names (Owner Name, Owner Mailing Address), and address fields (Site Address). Use it for owner-name lookups and address-based parcel searches. 4 of 9 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 2026-10-03.
/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 St. Louis city actually publishes, not what you might expect from a national standard (there isn't one).
For background, see What is an APN?
maps8.stlouis-mo.gov serves St. Louis city, Missouri 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 St. Louis city's MapServer layer on 2026-10-03. 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.
St. Louis city's layer is hosted by the county on maps8.stlouis-mo.gov. Public ArcGIS endpoints rarely rate-limit individual reads, but maps8.stlouis-mo.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.