In Baltimore City and the surrounding counties, most plumbing work beyond like-for-like fixture replacement needs a permit, including water heaters, new lines, gas piping and sewer work. The licensed contractor normally pulls the permit from the city or county office and arranges the inspection.
Which plumbing jobs need a permit?
Rules vary by jurisdiction, but as a general guide:
| Usually needs a permit | Usually doesn't |
|---|---|
|
|
Always confirm with your local office before starting work.
Where to get a plumbing permit, by area
| Area | Permit office |
|---|---|
| Baltimore City | Department of Housing & Community Development, Permits and Inspections |
| Baltimore County | Department of Permits, Approvals and Inspections, 111 West Chesapeake Avenue, Towson |
| Anne Arundel County | Department of Inspections and Permits, 2664 Riva Road, Annapolis. Homes inside Annapolis city limits may also need city review. |
| Howard County | Department of Inspections, Licenses and Permits, 3430 Court House Drive, Ellicott City |
| Harford County | Permits Center, 220 S. Main Street, Bel Air |
| Carroll County | County permits office, 225 North Center Street, Westminster |
| Queen Anne's County | County permits office, 208 N. Commerce Street, Centreville |
| City of Laurel (Prince George's County) | WSSC Water |
Office details are taken from the Maryland Department of Labor's list of local plumbing boards and county websites, checked 8 October 2026.
Who pulls the permit?
The licensed contractor doing the work normally applies for the permit and arranges the inspection. Be cautious if a contractor suggests skipping a permit for work that needs one: unpermitted work can cause problems with insurance claims and when you sell the house.
How to check a plumber's Maryland license
Maryland licenses master plumbers, journeyman plumbers and gas fitters through the State Board of Plumbing, part of the Maryland Department of Labor. Ask for the license number and look it up before work begins. Some jurisdictions also run their own local plumbing licensing: Carroll County issues local plumbing licenses, and WSSC Water licenses plumbers working in its service area, including the City of Laurel.
Inspections
Most permitted plumbing work is inspected at least once, often at rough-in (before walls are closed) and again at final. Keep the permit and inspection records with your house documents.
Frequently asked questions
Do I need a permit to replace a water heater in Maryland?
In most Maryland jurisdictions, yes. The contractor typically pulls the permit and the installation is inspected for venting, relief valve discharge and other code items.
Can a homeowner pull their own plumbing permit?
Some jurisdictions allow homeowners to do certain work on their own single-family home with a permit. Rules differ, so ask your local permit office first.
How do I look up a plumber's license?
Use the Maryland Department of Labor's license search for the State Board of Plumbing, and check any local license that applies where you live.