NY county/municipal open data portal directory

DRAFT. First research pass completed 2026-07-06 per research-plan-ny-open-data-portals.md. Covers all 57 non-NYC counties plus independent cities over ~50,000 population. Several entries are flagged UNCONFIRMED below — pending a manual browser check before this is cited externally. See Known gaps and caveats before relying on any single row.

Report generated: 2026-07-06 Data current as of: 2026-07-06

Directory of open data portals run by New York State counties and independent municipalities. NYC is out of scope here — see NYC Open Data and BetaNYC’s purpose-built MCPs instead.

A note on sorting: plain Markdown tables have no interactive sort — GitHub doesn’t add one either. The table below is sorted alphabetically (A→Z) by place name as a static substitute; a City of X entry sorts next to its county (e.g. “City of Albany” sits beside “Albany County”) rather than under “City.” The Region column lets you filter visually if you want one area at a time.

Legend

• API? Y — a machine-readable API is exposed (SODA, ArcGIS REST/GeoServices, WMS/WFS, CKAN API, etc.)
• API? N — download-only (CSV/PDF/shapefile) or a map-viewer app with no queryable catalog interface
• No portal found — a reasonable search turned up no true open-data catalog. Listed honestly, not omitted. Most of these counties still have some GIS web-mapping presence (a parcel viewer, a static shapefile download page) — see each row’s Notes.

Directory

Known gaps and caveats

This directory was compiled from six parallel regional research passes plus one targeted follow-up (Wayne County). Read this section before citing any single row externally.

1. Verification method. Most ArcGIS Hub/opendata.arcgis.com pages are JavaScript-rendered and returned only thin content or page titles to automated fetch tools. Platform and dataset confirmations mostly rely on: (a) DCAT-US JSON feed endpoints (/api/feed/dcat-us/1.1.json) where available — the strongest evidence used, since it lists real dataset counts; (b) HTTP header/HTML-marker fingerprinting (e.g., Socrata’s X-Socrata-Region header, socrata.com footer links, ArcGIS/Esri branding strings); (c) search-result snippets describing specific dataset names. None of this substitutes for a human clicking through the live page. A live browser check (Claude in Chrome) was available but not used broadly this session — it requires selecting among multiple connected browser profiles, a choice better made once, deliberately, rather than repeatedly mid-research.

2. Rows marked UNCONFIRMED need a direct manual check before being cited in any public-facing material: Westchester County (dual Hub instance), Rockland County (API classification), Orange County (dual Hub instance), Columbia County (dual Hub instance — Planning vs. Land Information Dept.), City of Schenectady (likely-stale cross-referenced document), Franklin County (subdomain naming is unexplained), Montgomery County (four visually similar candidate URLs, several belonging to Montgomery Co. PA).

3. Cross-state name collisions actively caught and excluded: Essex County NY vs. Essex County, Ontario (Canada); Washington County NY vs. Washington County, Wisconsin; Allegany County NY vs. Allegheny County PA/MD; Tioga County NY vs. Tioga County PA; Fulton County NY vs. Fulton County GA/IL/IN; Delaware County NY vs. Delaware County OH/PA and the State of Delaware. This class of error is easy to reproduce in a follow-up search — worth double-checking if this directory is regenerated later.

4. “No portal found” is common, not rare. Roughly half of NY’s counties have no browsable open-data catalog — most rely on a bare GIS map-viewer app (ArcGIS Web AppViewer/Experience Builder), a paid subscription parcel-lookup product (Schneider/Beacon, SDG), or the state’s own NYS GIS Clearinghouse (data.gis.ny.gov) as their de facto public data-sharing mechanism. These are documented in each row’s Notes rather than treated as a research failure.

5. The state-level Clearinghouse is not counted as county coverage. Rensselaer, Saratoga, Schenectady County, and Schoharie all rely on the NYS GIS Clearinghouse for their public GIS layers. That’s a state platform aggregating county-submitted data, not a county-run portal — marked “No portal found” here on that basis. Reasonable people could count this differently; flagging the judgment call.

6. Regional grouping note. Regions in the table above roughly follow common colloquial NY regional names, not a single official standard — Columbia and Greene counties, for instance, are geographically Hudson Valley but grouped once under Capital Region (matching NYS’s own Regional Economic Development Council convention) to avoid double-counting real duplicates found across two independent research passes.

Next steps

• Manual browser verification of the UNCONFIRMED rows above (a good candidate for a focused /deep-research or a quick Claude-in-Chrome pass once a browser profile is chosen)
• Consider whether the NYS GIS Clearinghouse deserves its own row as a statewide fallback resource
• Revisit “no portal found” counties periodically — GIS/open-data adoption in smaller counties changes over time