Enter a Maryland street address to identify the county, municipal boundary, zoning authority, permitting authority where verified, current ADU status, and the correct Maryland ADU Guide resource. This tool uses Maryland government GIS services rather than ZIP-code assumptions. It is a planning router, not a legal zoning determination.
Maryland ADU True Jurisdiction Finder
Which local government actually controls your ADU?
A mailing city or ZIP code can be misleading. This finder geocodes the property, checks Maryland’s county and municipal boundary layers, then separates zoning authority from building-permit authority.
Last source review: September 10, 2026. Boundary routing uses Maryland government GIS data; authority labels are shown only where the planning or permitting path has been verified, otherwise the finder says verification is still needed.
What this finder can — and cannot — determine
The tool can resolve an address against Maryland's official county and municipal boundary datasets and route the user to a verified planning authority where our authority matrix is supported. It does not determine a parcel's zoning district, setbacks, Critical Area status, floodplain, septic capacity, HOA rules or permit eligibility. Those belong in the next stage of the Maryland ADU planning workflow.