Free parcel data in Montana
Yes. Montana publishes a free statewide parcel layer: Montana Cadastral Framework - Montana Parcels, from Montana State Library (MSDI Cadastral), data from Montana Department of Revenue ORION. Coverage: All 56 counties (Revenue-maintained; Ravalli, Silver Bow, Missoula, Flathead, Yellowstone county-maintained, integrated by MSL). It's a public ArcGIS REST service with no API key or login.
The layer
| Layer | Montana Cadastral Framework - Montana Parcels |
|---|---|
| Publisher | Montana State Library (MSDI Cadastral), data from Montana Department of Revenue ORION |
| Coverage | All 56 counties (Revenue-maintained; Ravalli, Silver Bow, Missoula, Flathead, Yellowstone county-maintained, integrated by MSL) |
| Data vintage | TaxYear 2026; updated monthly |
| Terms | Public; attribution: Montana State Library, Department of Revenue |
| Fields | parcel number (PARCELID, AssessmentCode, PropertyID); site address (AddressLine1); owner (OwnerName); legal description; subdivision |
| Not published | deed references, plat references |
| REST endpoint | https://gisservice.mt.gov/arcgis/rest/services/msdi_cadastral_map_v1/MapServer/1 |
| Last verified | 2026-10-19 with a live point and parcel-number query |
Notes for GIS users
PARCELID is the 17-digit geocode stored without dashes (users often write it as 06-0798-12-4-42-17-0000; strip dashes before querying). CityStateZip is combined, e.g. 'BOZEMAN, MT 59715'. Unparceled polygons (roads/ROW/water) come back with null PARCELID; treat as no parcel. Same data also at services.arcgis.com/qnjIrwR8z5Izc0ij/.../Montana_Cadastral_Framework/FeatureServer/1 (maxRecordCount 1000).
How to use it
- QGIS: Layer > Data Source Manager > ArcGIS REST Server, add a connection with the service URL (the endpoint above without the
final
/0), then add the layer. Filter to your area before exporting. - ArcGIS Pro: Add Data > Data From Path, paste the endpoint.
- Direct query: append
/query?geometry=LON,LAT&geometryType=esriGeometryPoint&inSR=4326&spatialRel=esriSpatialRelIntersects&outFields=*&f=geojsonto get the parcel at a point. - CAD: see getting a parcel into AutoCAD or Civil 3D.
Assessor parcel lines are for taxation and are often 5 to 50 ft off the legal boundary. Why.
Basesheet uses this to draw the parcel line on a base plan for any Montana address, with LiDAR contours, soils, flood zones and wetlands.
Build a base plan