Building permits in Montgomery County, Maryland
Find the right authority before you build. Montgomery County permitting follows Maryland law — here is exactly who issues the permit and where to start.
County issues permits
Montgomery County Department of Permitting Services (DPS)
Montgomery County issues building permits through its Department of Permitting Services for properties countywide. Unlike many states, Maryland counties (not cities) serve as the primary permit authority, and municipalities in Montgomery County rely on county permitting.
Open the official permit portal →
DPS offers online application/ePermits, a Residential Fast Track for projects ≤400 sq ft, and free design consultations.
Check a home project's permit in Montgomery County, Maryland
Select a project to see its Maryland permit rule. Whether the county or your city issues it depends on incorporation status — see the authority note above.
Maryland
Exact permit fees are set by the local building department. WikEst shows the published or code-based range where one exists, linked to its official source — verify the final amount at the source before budgeting.
🏠 Accessory Dwelling Unit (ADU) permit fee in Maryland
Permit requiredCase by casecity authority
Permit fee range
Building permit fee set by the city; zoning/use approval also required.
Typical timeline
Varies
Setback
—
Exempt if
Not size-exempt
ADUs require a building permit and local zoning approval. Maryland’s MBPS governs construction; local zoning controls whether an ADU is allowed. Verify with Baltimore DHCD or Annapolis Planning & Zoning.
Official sources: Maryland Dept. of Labor — Building Performance Standards (state building code) · Baltimore City — Dept. of Housing & Community Development (permits)
Representative cities for Maryland: Baltimore, Annapolis.
All 20 project fee ranges in Maryland
Official-source ranges where published; “By local jurisdiction” means no flat fee is published and the amount is set case by case.
| Project | Permit? | Authority | Fee range | Go / no-go |
|---|---|---|---|---|
| 🏠 Accessory Dwelling Unit (ADU) | yes | city | Building permit fee set by the city; zoning/use approval also required. | case-by-case |
| 🪵 Deck / Porch | conditional | city | Set by the city. | allowed |
| 🧱 Fence / Wall | conditional | city | Set by local jurisdiction | allowed |
| 🛖 Shed / Outbuilding | conditional | city | Set by local jurisdiction | allowed |
| 🪜 Basement Finish | yes | city | Building permit fee set by the city. | allowed |
| 🚗 Garage / Carport | yes | city | Building permit fee set by the city; zoning clearance may be required. | allowed |
| ☀️ Rooftop Solar PV | yes | city | Electrical/structural permit fee set by the city. | allowed |
| 🌡️ HVAC Replacement | yes | city | Mechanical permit fee set by the city. | allowed |
| 🍳 Kitchen Remodel | yes | city | Building permit fee; trade permits billed separately. | allowed |
| 🛁 Bathroom Remodel | yes | city | Building permit fee; trade permits billed separately. | allowed |
| 🏗️ Room Addition | yes | city | Building permit fee based on valuation; zoning and plan review apply. | allowed |
| 🪟 Window / Door Replacement | conditional | city | Set by local jurisdiction | allowed |
| 🏘️ Roof Replacement | yes | city | Roof-covering permit fee set by the city. | allowed |
| 🅿️ Driveway / Parking Pad | conditional | city | Set by local jurisdiction | allowed |
| 🏊 Swimming Pool / Spa | yes | city | Building permit fee; barrier fencing required by code. | allowed |
| 🧱 Retaining Wall | conditional | city | Set by local jurisdiction | allowed |
| 💥 Demolition / Teardown | yes | city | Demolition permit fee set by the city. | allowed |
| 🚰 Septic System | yes | state | Onsite disposal system (septic) permit fee set by the Maryland Dept. of the Environment / local health department. | allowed |
| 🔌 EV Charger | conditional | city | Electrical permit fee set by the city. | allowed |
| ⚡ Standby Generator | conditional | city | Mechanical and/or electrical permit fee set by the city. | allowed |
Permit cheat-sheet (Maryland rules)
| Project | Permit? | Authority | Typical fee | Timeline | Go / No-Go | Key notes |
|---|---|---|---|---|---|---|
| 🏠 Accessory Dwelling Unit (ADU) | Permit required | city | Building permit fee set by the city; zoning/use approval also required. | — | Case by case | ADUs require a building permit and local zoning approval. Maryland’s MBPS governs construction; local zoning controls whether an ADU is allowed. Verify with Baltimore DHCD or Annapolis Planning & Zoning. |
| 🪵 Deck / Porch | Conditional | city | Set by the city. | — | Generally allowed | Attached decks and decks over 30 in above grade need a permit. Annapolis publishes deck construction requirements. Exempt: Decks over 30 in above grade generally require a building permit under the IRC (adopted in MD as MBPS). |
| 🧱 Fence / Wall | Conditional | city | — | — | Generally allowed | Most Maryland jurisdictions do not require a building permit for fences, but height and front-yard limits are set locally. Verify with your city. |
| 🛖 Shed / Outbuilding | Conditional | city | — | — | Generally allowed | Detached accessory sheds below the local size threshold are generally exempt. Annapolis publishes shed building requirements. Exempt: Many jurisdictions exempt small detached sheds (commonly under ~120–200 sq ft). |
| 🪜 Basement Finish | Permit required | city | Building permit fee set by the city. | — | Generally allowed | Finishing a basement into habitable space requires permits for egress, framing, electrical, plumbing, and mechanical work. |
| 🚗 Garage / Carport | Permit required | city | Building permit fee set by the city; zoning clearance may be required. | — | Generally allowed | A new attached or detached garage requires a building permit. |
| ☀️ Rooftop Solar PV | Permit required | city | Electrical/structural permit fee set by the city. | — | Generally allowed | Rooftop solar PV requires an electrical and structural permit, reviewed locally. |
| 🌡️ HVAC Replacement | Permit required | city | Mechanical permit fee set by the city. | — | Generally allowed | Furnace, AC, or heat-pump replacement requires a mechanical permit and inspection. |
| 🍳 Kitchen Remodel | Permit required | city | Building permit fee; trade permits billed separately. | — | Generally allowed | A permit is required when relocating plumbing/electrical, moving walls, or changing fixtures. |
| 🛁 Bathroom Remodel | Permit required | city | Building permit fee; trade permits billed separately. | — | Generally allowed | A permit is required when relocating plumbing/electrical, moving walls, or changing fixtures. |
| 🏗️ Room Addition | Permit required | city | Building permit fee based on valuation; zoning and plan review apply. | — | Generally allowed | Room additions require a full building permit, zoning approval, and usually a site plan. |
| 🪟 Window / Door Replacement | Conditional | city | — | — | Generally allowed | Swapping windows or exterior doors in the same opening is generally exempt; enlarging openings requires a permit. |
| 🏘️ Roof Replacement | Permit required | city | Roof-covering permit fee set by the city. | — | Generally allowed | Roof covering replacement is typically permitted. Minor leak repairs may be exempt. |
| 🅿️ Driveway / Parking Pad | Conditional | city | — | — | Generally allowed | A permit may be required where the driveway connects to the street/right-of-way or involves grading/excavation. Verify locally. |
| 🏊 Swimming Pool / Spa | Permit required | city | Building permit fee; barrier fencing required by code. | — | Generally allowed | In-ground and above-ground pools need a permit and barrier fencing per local code. |
| 🧱 Retaining Wall | Conditional | city | — | — | Generally allowed | Height and surcharge determine the threshold. Annapolis requires sheeting/shoring permits for adjacent excavations. Verify with your city. |
| 💥 Demolition / Teardown | Permit required | city | Demolition permit fee set by the city. | — | Generally allowed | A full or partial structural demolition (house, garage) requires a demolition permit from the local building department, with utility disconnects, asbestos/lead-paint clearance for pre-1978 homes, and erosion/sediment controls as applicable. Verify with Baltimore DHCD or Annapolis. |
| 🚰 Septic System | Permit required | state | Onsite disposal system (septic) permit fee set by the Maryland Dept. of the Environment / local health department. | — | Generally allowed | New or replacement onsite wastewater (septic) systems in Maryland are permitted through the Maryland Dept. of the Environment Onsite Disposal Systems (OSDS) program, typically administered by the county health department (not the building department). A site evaluation and soil/load test are required before design and installation. |
| 🔌 EV Charger | Conditional | city | Electrical permit fee set by the city. | — | Generally allowed | A home EV charging station generally requires an electrical permit under the Maryland Building Performance Standards (MBPS, adopting the IRC/NEC Article 625) for the new branch circuit, disconnect, and equipment. Some Maryland jurisdictions (e.g., Montgomery County) have local EV-ready requirements. Verify with your local building department. |
| ⚡ Standby Generator | Conditional | city | Mechanical and/or electrical permit fee set by the city. | — | Generally allowed | A permanently installed standby generator requires mechanical and electrical permits (NEC Articles 445/702) covering the transfer switch, gas/propane line, and connection. Verify with your local building department. |
Frequently asked questions
Who issues building permits in Montgomery County, Maryland?
Montgomery County Department of Permitting Services (DPS) is the permitting authority for Montgomery County. The county issues permits for both unincorporated areas and incorporated cities. Start at the official portal linked above.
Do I go to the county or my city for a building permit in Montgomery County?
The county issues permits for both unincorporated areas and incorporated cities.
What home projects need a permit in Montgomery County?
The same project types shown in the cheat-sheet above (ADU, deck, fence, shed, solar, and more) — rules follow Maryland state law. Whether the county or your city issues it depends on your property's incorporation status.
How do I apply for a permit in Montgomery County?
Use the official permit portal linked above. Most offices accept online submissions; have your plans, site information, and contractor details ready before applying.