Free parcel data in Maryland

Yes. Maryland publishes a free statewide parcel layer: Maryland Parcel Boundaries, from MD iMAP / Maryland Department of Planning, with SDAT assessments. Coverage: All 23 counties + Baltimore City (24 JURSCODE values). It's a public ArcGIS REST service with no API key or login.

The layer

Layer	Maryland Parcel Boundaries
Publisher	MD iMAP / Maryland Department of Planning, with SDAT assessments
Coverage	All 23 counties + Baltimore City (24 JURSCODE values)
Data vintage	SDAT assessments May 2026 (SDATDATE '2026MAY')
Terms	Public; attribution: MD iMAP, Maryland Department of Planning, SDAT
Fields	parcel number (ACCTID, PARCEL); site address (ADDRESS); plat reference; legal description; subdivision
Not published	owner names, deed references
REST endpoint	`https://mdgeodata.md.gov/imap/rest/services/PlanningCadastre/MD_ParcelBoundaries/MapServer/0`
Last verified	2026-10-19 with a live point and parcel-number query

Notes for GIS users

ACCTID is the SDAT account id (statewide unique, county prefix). PARCEL is only unique within a county MAP/GRID. JURSCODE is a 4-letter code (ANNE, BACI = Baltimore City, BACO = Baltimore County, MONT, PRIN, ...). Also reachable at geodata.md.gov.

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=geojson to 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 Maryland address, with LiDAR contours, soils, flood zones and wetlands.

Build a base plan