Public ArcGIS MapServer endpoint for Union County 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 Union County parcel search runs this same layer in your browser, no account and no API key.
Search Union County parcelsHave a street address but not the parcel number? Find the parcel number by address.
https://gis.mississippi.edu/server/rest/services/Cadastral/MS_MDEQPARCELS_East_2024/MapServer/0Field by field, whether any endpoint we index for Union County 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. |
PARNOParcel NumberOWNNAMEOwner NameSITEADDSite Addresscurl -s 'https://gis.mississippi.edu/server/rest/services/Cadastral/MS_MDEQPARCELS_East_2024/MapServer/0/query?where=STCNTYFIPS+%3D+%2728145%27+AND+FID+%3D+1004392&outFields=*&returnGeometry=false&f=json'
https://gis.mississippi.edu/server/rest/services/Cadastral/MS_MDEQPARCELS_East_2024/MapServer/0/query?where=STCNTYFIPS+=+'28145'+AND+FID+=+1004392&outFields=*&returnGeometry=false&f=jsonOpen this URL in a browser tab to see the raw ArcGIS JSON response.
| Field name | Label | Searchable |
|---|---|---|
| PARNO | Parcel Number | YES |
| OWNNAME | Owner Name | YES |
| SITEADD | Site Address | YES |
| SCITY | Site City | NO |
| SSTATE | Site State | NO |
| SZIP | Site ZIP | NO |
| MAILADD1 | Owner Mailing Address | NO |
| MCITY1 | Owner Mailing City | NO |
| MSTATE1 | Owner Mailing State | NO |
| MZIP1 | Owner Mailing ZIP | NO |
| STCNTYFIPS | County FIPS | NO |
| TAXYEAR | Tax Year | NO |
Union County, Mississippi (FIPS 28145). Served by the MARIS/MDEQ 2024 statewide cadastral layer (East half, MS_MDEQPARCELS_East_2024 MapServer layer 0 on gis.mississippi.edu), compiled from the county tax assessors' rolls and republished by MARIS; credit the Union County Tax Assessor's office and MARIS/MDEQ. The layer carries all 44 eastern counties (1,127,050 parcels), so every attribute search here is scoped with STCNTYFIPS = '28145' (20,321 parcels read 2026-10-12). Informational only and not a legal record: verify with the Union County Tax Assessor, whose roll is the authoritative source. The layer refuses pagination (any resultRecordCount or resultOffset returns HTTP 200 with error 400 "Pagination is not supported.") and answers at most 2,000 rows per request, setting exceededTransferLimit on a cut; orderByFields and returnDistinctValues are ignored without an error, outStatistics fails, and returnCountOnly, returnIdsOnly and objectIds work. A FID equality or a read scoped by FIPS plus a FID range answers in 70 to 550 ms, and a count over a FIPS-plus-FID range in about 1.1 s. A PARNO equality or any other non-FID predicate scans the whole statewide layer and takes 1.3 s to more than 20 s, more on the first query after hours idle, so scope anything else with STCNTYFIPS plus a FID range or objectIds. The server rejects FID BETWEEN (HTTP 200 with error 400 "Failed to execute query."); write the range as FID >= a AND FID <= b. OWNNAME and SITEADD are each filled on 99.9% of rows (20,299), with SCITY, SSTATE and SZIP beside them. Across the statewide layer SITEADD carries the vacant-land placeholders '0' and '0 <STREET>' on some rows (about 48% in Hancock, 26% in Lamar, 11% in DeSoto), so a non-empty SITEADD can be a placeholder. PARNO may carry stray leading or embedded whitespace (measured in Alcorn), so match it with LIKE or trim before an equality. Mailing address columns mapped: MAILADD1 is filled on 95.5% of rows (19,404). We read 25 rows on 2026-10-13; 22 were street-like (a house number or a PO Box), under the 90% the atlas requires. A second sample of 50 rows from a different FID window came back 46 of 50, so the columns are mapped. The city, state and ZIP columns are mapped with it. CORS: the server echoes any request Origin, so browser tools call it directly. License: the portal item declares none and the MARIS disclaimer (the licenseUrl) states no redistribution or attribution terms; the data is public, free and keyless.
Mississippi Automated Resource Information System (MARIS), hosted by MDEQ Office of Geology, Geospatial Resources Division, https://maris.mississippi.edu/
Union County's MS_East_MDEQPARCELS_2024 layer exposes a parcel identifier (Parcel Number), owner names (Owner Name), and address fields (Site Address). Use it for owner-name lookups and address-based parcel searches. 3 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 2026-10-13.
/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 Union County actually publishes, not what you might expect from a national standard (there isn't one).
For background, see What is an APN?
gis.mississippi.edu serves Union County, Mississippi 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 Union County's MapServer layer on 2026-10-13. 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.
Union County's layer is hosted by the county on gis.mississippi.edu. Public ArcGIS endpoints rarely rate-limit individual reads, but gis.mississippi.edu 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.