How Do I Find My Main Water Shut-Off Valve?

Swimming is great, but you probably don’t want to do it in your living room. Knowing where to find the shut-off valve in your house can save you from a potential flood fiasco if a water pipe bursts. In most homes, the main water shut-off valve can be found near the water meter, often located in the basement or near the water heater. However, the exact location of the valve depends on your foundation type. 

Where to Find the Water Shut-Off Valve by Foundation Type

The main water shut-off valve looks like a lever or wheel-like handle attached to a pipe near where the water supply enters your home. It’s usually larger and more robust than other valves in your plumbing system. 

The exact location of the main water shut-off valve depends on the house’s foundation type because of plumbing layout differences. Here’s where you can find the valve based on your home’s foundation type.

Slab Foundation 

If your house is on a slab, your main water shut-off valve should be near your water heater tank, either under it or at the top. You might find the water heater in a utility closet and the valve may be behind an access panel.

Basement

If you have a basement, that’s probably where you’ll find your shut-off valve. Most water valves in the basement will be in the same place as your outdoor hose bib, just on the inside of the wall.

The easiest way to find the valve is to picture where the hose attachment is on the outside of the house. Then find the corresponding spot on the wall inside the house. 

Crawl Space

Homes with crawl spaces have a raised foundation with a space beneath the meain floor, where the main water shut-off valve might be located. You can usually find the valve along the front wall of the house.

• With basement: The shut-off valve is wherever water enters your basement.

• Without basement: The shut-off valve is near the water heater or under the kitchen sink.

Pier and Beam

Pier and beam foundations combine elements of slab and crawl space construction. In these homes, the main water shut-off valve is near the water entry point, which may be in a utility area under the house or in a basement if the house has one. It’s usually conveniently accessible from inside the house. 

How to Turn Off the Water Valve

Depending on the type of water valve you have, you’ll turn it off a little bit differently.

Ball Valve

A ball valve contains a ball with a hole through the middle of it. When you turn the long lever handle to turn the valve on, the hole in the ball aligns with the water pipe and allows water to flow. When the valve is closed, the ball turns and blocks the pipe. 

Turn the handle 90 degrees to the right to shut off the valve, or turn it 90 degrees to the left to open it. 

Gate Valve

Gate valves have round handles that control a gate that moves up and down inside the valve to allow or block the flow of water. You can adjust the flow of water or completely turn it off. Turn the handle counterclockwise as far as possible to open it, and turn it clockwise to close it. Never force it since you could damage the handle and valve. 

Streetside Ground-Level Utility Box

If you still aren’t able to find and turn off your water shut-off valve, you may be able to locate and turn off the valve in the streetside ground-level utility box. The valve in this box, also known as a curb valve, is at the beginning of your water main. You should see a plastic or metal door at the top of the box. 

There’s usually a phone number on the door for emergency services at your water company. You can call and ask how to shut off the valve, or they can send an emergency team to assist you. 

Tips for Locating Your Main Water Shut-Off Valve

If you still aren’t sure where to find your main water shut-off valve, here are some tips for scoping it out:

• Walk along the inside perimeter of your home and look for where plumbing comes into the house.

• Check near the water meter, which is usually installed near the front of your property, then look for a valve on the main water line leading into the house.

• Look in utility areas, particularly for homes with crawl spaces, basements, or utility closets.

• Consider exterior locations—especially for older homes, the shut-off valve may be located in a valve box or access point near the exterior water supply line.

• Go through your file cabinet to find the property inspection report if you own the home or call your landlord if you’re renting.

Alternatives to Your Main Water Shut-Off Valve

If you can’t locate the main water shut-off valve, don’t panic. You can hire a plumber near you to take a look or an emergency service if you have an urgent leak. There are some alternatives to consider as well, like valves that shut off water to specific fixtures. 

Turn Off Isolation Valves

If a specific fixture or appliance is leaking, like the toilet, bathtub, sink, or washer, you can look nearby along the wall or under the fixture for isolation or service valves to shut off water just to one specific plumbing fixture.

To turn off water to a toilet, you can usually find the water supply valve on the wall or floor adjacent to the toilet. You can turn the shut-off values for a bathtub if you can get to the plumbing via an access panel. Under a sink, you’ll find shut-off valves for the hot and cold water. For a washer, look for shut-off valves behind or above the unit. 

Consider the City Shut-Off Valve

In the ground on your property or near the sidewalk, there is a city shut-off valve for the water to your property. While it’s illegal to shut this off yourself without calling the emergency service line, you can make that call, and they will direct you to shut off the water via this valve or send an emergency team to do it for you.

Terri Beth Miller contributed to a previous version of this article.