ADU Rules in Maryland (2026)
ADU rules in Maryland — no statewide ADU law. Regulation is entirely local. Key provisions and city-specific frameworks for accessory dwelling units.
Law Name
Preempts Local Ordinances
No — local rules may be stricter
Has State Law
No — regulation is local
Statewide Preemption Status Unconfirmed
No statewide preemption statute was confirmed for this jurisdiction — regulation is local. Local governments retain full authority to set their own rules.
Local Control Framework
Maryland does not have a statewide ADU preemption law as of 2026 · Source
ADU regulation is left to local jurisdictions — each county and municipality sets its own rules · Source
Montgomery County, Prince George's County, and Baltimore City have their own ADU ordinances · Source
Maryland has been actively discussing statewide housing reform legislation but comprehensive ADU mandates have not passed as of 2026 · Source
Maryland Department of Housing and Community Development provides guidance and incentives for affordable housing including ADUs · Source
Legislative History
2023 — Various Maryland Housing Reform Bills (proposed, not enacted as ADU mandate) · Source
Maryland Legislature considered several housing supply bills including ADU by-right provisions but a comprehensive statewide ADU preemption law had not been enacted by 2026. Local jurisdictions retain control. · Source
Source: Maryland Local Zoning Authority. Last verified April 5, 2026. View source