Proudly Serving Maryland, DC & NoVa for 46 Years
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#1 Rated plumbing services

Searching for Licensed Local Plumbers in Maryland, DC and NoVA?

Serving Montgomery, Howard, Frederick, Baltimore, Carroll, Prince George’s Counties in Maryland, District of Columbia & Northern Virginia

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Maryland, DC & Northern VA

Plumbing & Mechanical

A Rheem Ikonic tankless water heater with a silver rectangular body, control panel display, and two pipe connections on top, designed for wall-mounted installation and enhanced with advanced leak detection features.

Tankless Water Heater

A tall, cylindrical gray water heater with a digital display, multiple access panels, and the Rheem logo on the front. The unit features gas fitting connections and connection points for pipes at the top and bottom.

Hybrid Water Heater

A tall, cylindrical water heater with a digital display on top, several valves and connectors, and a small attached control box at the bottom. This advanced water heater stands upright against a white background, ideal for modern water heaters setups.

Gas Water Heater

A tall, cylindrical gray AO Smith water heater with a control knob at the bottom, two large rectangular panels on the front, labeled hot and cold water connections on top, and designed for easy leak detection and other plumbing needs.

Electric Water Heater

Five different chrome or stainless steel kitchen faucets are displayed side by side on a white background, each with a unique design and shape, like those featured in the National Water Service Gallery.

Faucet Installation & Repair

A blue flexible gas hose with gas fitting and metal fittings, various connectors, brass coupling, elbow joint, mounting hardware, washers, screws, two carabiners, and a coiled blue lanyard arranged on a white background. Ideal for water heaters.

Gas Fitting

A yellow pipe inspection camera system with a reel of black cable, a metal handle, and a mounted monitor on top, designed for plumbing tasks such as leak detection or sewer inspections.

Camera Inspection

A red and black Milwaukee drain cleaning machine with a coiled cable, battery, charger, two drain cleaning tool attachments, and a set of keys—ideal for plumbing tasks like leak detection—displayed on a white background.

Drain Cleaning & Fixtures

A black Flotec Professional submersible sump pump with a float switch attached, designed for water removal applications—an essential in plumbing systems where reliable sump pumps are needed.

Sump Pumps

A black electronic device labeled DROP, designed for leak detection, with a blue water droplet inside the letter O, shown from above on a white background.

Leak Detection

A gray InSinkErator garbage disposal unit with 3/4 HP and Advanced Series Evolution 750 labeled on the side, featuring a metallic mounting assembly at the top—ideal for modern plumbing setups.

Garbage Disposal

L-shaped outdoor kitchen set featuring a built-in grill, sink with advanced plumbing for easy leak detection, storage cabinets, a refrigerator with blue-lit interior, and a beer tap on a white background.

Outdoor Kitchen

A pipe wrench, plumbing valve, and fittings rest on a pair of gray work gloves, essentials for expert plumbing or gas fitting tasks, displayed on a white background.

Residential Plumbing

A plumber wearing jeans, a blue shirt, and a cap kneels on the floor, repairing pipes under a kitchen sink. A tool bag sits on the counter above him. The setting features wooden cabinets and a brick wall.

Emeregency Plumbing

A collection of various stainless steel pipe fittings and connectors, including elbows, tees, and threaded parts for plumbing or water heaters, arranged on a neutral background.

Commercial Plumbing

And More!

Plumbing Repair

Plumbing Install

Emergency Plumbing Services

What plumbing services do you provide in Maryland, DC & NoVA?

We handle a full range of plumbing and mechanical services, including tankless, hybrid, and gas water heaters, faucet installation, gas fitting, drain cleaning and repairs, sump pumps, leak detection, garbage disposals, outdoor kitchens, residential plumbing, commercial plumbing, emergency plumbing, and more.

We provide plumbing services throughout Maryland, Washington, DC, and Northern Virginia, with a strong focus on counties like Montgomery, Howard, Frederick, Baltimore, and Carroll and many surrounding cities and communities.

Yes. If you have no water, a major leak, sewage backup, or any urgent plumbing issue, you can contact us for emergency plumbing service. A licensed plumber will be dispatched as quickly as possible to help protect your home or business from further damage.

Yes. Our plumbers are fully licensed and insured and follow all local codes and regulations. Our company holds plumbing and contractor licenses in Maryland and Virginia, and we stay up to date on best practices and safety standards.

National Water Service has been serving homeowners and businesses for over 47+ Years, providing expert plumbing, water treatment, and mechanical services backed by precision workmanship and trusted customer service.

Absolutely. We service single-family homes, townhomes, condos, apartments, offices, retail spaces, and other commercial properties. Whether you need routine maintenance at home or a large installation at a commercial site, we can help.

Yes. We install, repair, and replace tankless water heaters, hybrid water heaters, and traditional gas water heaters. Our team can help you choose the right size and type of system based on your home or business, hot water usage, and energy-efficiency goals.

Yes. We provide drain cleaning and repair for slow drains, recurring clogs, gurgling drains, and backups in sinks, tubs, showers, and toilets. We’ll diagnose the cause of the problem and recommend the best long-term fix, not just a quick temporary solution.

Yes. We offer professional leak detection services. If you see unexplained water spots, higher water bills, damp areas, or hear water running when fixtures are off, we can locate and repair hidden leaks in pipes, walls, floors, or underground lines.

Yes. We offer professional leak detection services. If you see unexplained water spots, higher water bills, damp areas, or hear water running when fixtures are off, we can locate and repair hidden leaks in pipes, walls, floors, or underground lines.

You can schedule a service by using the “Schedule a Service” button on our website or by calling our office during business hours. Just share your contact information, address, and the nature of your plumbing issue, and our team will confirm an appointment time with you.

Our standard office and service hours are Monday–Thursday, 7:00am–5:00pm, and Friday, 7:00am–4:00pm. Emergency plumbing service is available on weekends as needed.

Yes. In addition to plumbing and mechanical work, National Water Service specializes in water treatment systems and well pump services. If your property uses a well or you’re concerned about water quality, we can design, install, and maintain a complete solution for clean, reliable water.

We provide upfront, competitive pricing before work begins. After inspecting the issue, our technician will explain your options and associated costs so you can make an informed decision—no surprise charges or hidden fees.

If safe to do so, turn off the water supply to the affected fixture or your main water shutoff valve, avoid using electrical outlets near standing water, and move valuables away from the leak area. Then contact us immediately so we can dispatch an emergency plumber.

Coupons

An older man in military uniform salutes while facing a large American flag, blurred in the background—honoring service much like the dedication seen at the National Water Service.

$ 25 OFF

Installation and Service

For Active Duty Military, Veterans Or First Responders

A home water filtration and softener system is mounted on a wooden wall, featuring pipes, filters, a large white tank, two tall black and grey cylinders, control panels, and various components for water treatment.

$ 75 OFF

New Water Treatment

For New Customers Getting New Water Treatment Installs Only

A white plastic pipe with a capped top stands upright on a grassy lawn near a residential street, possibly related to leak detection services, with houses and trees visible in the background.

$ 100 OFF

New Well Pumps Installation

For New Customers Getting New Well Pump Installs Only

Two men stand at a table working together to repair or assemble an open electronic device. One man points while the other uses a tool, possibly for leak detection. Papers, a drink tumbler, and a thermos are on the table.

$ 25 OFF

Customer First Service Call

For New Customers Getting First Service Call

A plumber kneels on a cloth in a kitchen, working under the sink cabinet. Tools and cleaning supplies are on the counter, with a red plumbing machine in the foreground. The kitchen features wooden floors and dark wood cabinets.

$ 40 off

Any Plumbers Service Call

For use only one time per customer

National Water Service

2878 Daisy Road, Woodbine, Maryland, 21798

301-854-1333

Service Area

Counties:

Montgomery County, Howard County, Frederick County, Baltimore county and Carroll County in Maryland.

Fairfax County, Alexandria County, Manassas County, Falls Church County, Arlington County, Loudoun County in Virginia

Areas and cities:

Rockville, Bethesda, Potomac, Silver Spring, Columbia, Ellicott City, Clarksville, Woodbine, Savage, North Laurel, Dayton, Glenwood, Cooksville, Ilchester, West Friendship, Jessup, Lisbon, Highland, Woodstock, Elkridge, Sykesville, Marriottsville, Glenelg, Frederick, Urbana, and Middletown, Westminster, Sykesville, Eldersburg, New Windsor, Union Bridge, Hampstead, Manchester, Taneytown, Towson, Kingsville, White Marsh, Lochearn, Reisterstown, Dundalk, Accokeek, Adelphi, Andrews AFB, Aquasco, Baden, Beltsville, Bladensburg, Bowie, Brandywine, Brock Hall, Camp Springs, Capitol Heights, Cedar Heights, Cheltenham, Chillum, Clinton, Coral Hills, Croom, District Heights, East Riverdale, Fairmount Heights, Fairwood, Forestville, Fort Washington, Friendly, Glassmanor, Glenarden, Glenn Dale, Greenbelt, Hyattsville, Kettering, Konterra, Lake Arbor, Landover, Landover Hills, Langley Park, Lanham, Largo, Marlboro Meadows, Marlboro Village, Marlton, Mitchellville, National Harbor, Oxon Hill, Palmer Park, Peppermill Village, Queen Anne, Queens Chapel, Queensdale, Queensland, Riverdale, Riverdale Park, Rosaryville, Seat Pleasant, Seabrook, Silver Hill, Springdale, Suitland, Summerfield, Temple Hills, Upper Marlboro, Walker Mill, Westphalia, West Laurel and Woodmore.

Fairfax, Reston, Herndon, McLean, Vienna, Great Falls, Annandale, Springfield, Burke, Lorton, Chantilly, Centreville, Clifton, Oakton, Falls Church, Arlington, Alexandria, Ashburn, Sterling, Leesburg, Purcellville, Middleburg, South Riding, Aldie, Brambleton, Cascades, Broadlands, Lovettsville, Round Hill, Manassas, Manassas Park, Haymarket, Gainesville, and Falls Church City.

District of Columbia