How to shut off your main water valve
When water is spreading across the floor, you need the shutoff handled in seconds, not minutes. Find your main shutoff valve, then turn it the right way: a round wheel-style gate valve closes clockwise — turn it slowly and fully until it stops. A lever-style ball valve closes with a single quarter turn until the lever sits crosswise to the pipe. To turn the water back on, reverse it: open slowly so the system repressurizes without a hammer.
Keep the valve reachable. If a pipe bursts, you don't want to be climbing over stored boxes to get to it. Clear a path now and make sure everyone in the house knows where it is.
If water has already reached outlets, appliances, or the electrical panel, shut off the power at the main breaker before you wade in. Never touch a panel or breaker with wet hands or while standing in water.
Where is the main water shut-off valve?
The main valve sits where water enters your home, so it's usually near the perimeter of the house at or below ground level. If you can't spot it, follow the supply pipe from the street toward the house and it'll lead you there. In a basement, you'll typically find it near the front foundation wall, within three to five feet of where the main water line comes through the wall or floor 1.
Where exactly it sits depends on how your home is built:
- In newer homes, the customer shutoff is installed right next to the city's water meter box, in its own enclosure.
- With a basement, look near the front foundation wall — often within three to five feet of where the main line enters. Check the mechanical room or near the water heater and furnace.
- With a crawlspace and a basement, the valve is often inside the crawlspace rather than the basement.
- With a crawlspace but no basement, look under the kitchen sink or near the water heater.
- In slab-on-grade homes, it could be any of the above, but most often it's near the water heater or kitchen sink.
If your valve is in a crawlspace, plan ahead. Crawlspaces are cramped and can flood, which is the worst time to need a valve you can't reach. Install an access hatch, label the valve clearly, and show every adult in the house where it is. If reaching it means a real struggle, have a plumber add a second, easier-to-reach valve in the basement or utility room.
Who owns the valve — you or the city?
Most homes have two shutoffs on the main line. One sits just before the water meter, inside the meter box — that valve belongs to the city or water authority, and you generally aren't allowed to operate it. The other sits just after the meter, on your side, and that's the one you use to turn water on and off to the house.
If your home doesn't have a valve after the meter, have one installed. It's your first line of defense in an emergency and it keeps you off city property. If the city-owned valve is leaking or faulty, don't try to fix it yourself — report it to the water authority right away.
Types of shut-off valve: gate, ball, and globe
Knowing which valve you have tells you how to turn it and how much to trust it.
Most master shutoffs are either a gate valve, identified by a round wheel handle, or a ball valve, identified by a straight lever 2. Gate valves close slowly and are more prone to corrosion. Ball valves give a straight-through flow path and a quick quarter-turn, and they're more reliable over time 3. Some older or specialty valves operate differently — a few are marked "pull to close" right on the body, so check for printed instructions before you assume which way it works 4.
Globe valves are a third type, built to throttle flow rather than fully isolate it; they reduce pressure even when fully open and close slowly enough to avoid water hammer 5.
What the plumbing code requires
The International Plumbing Code spells out where shutoff valves have to be. That's useful when you're trying to figure out what should exist in your home.
Code requires full-open valves at the building entrance, on each branch line, and on the supply to each fixture and appliance 6. Shutoff valves are required on individual fixture supplies (except bathtubs and showers in one- and two-family homes), on each sill cock, and on each appliance 6. All of these valves must be accessible — not buried behind drywall or blocked by storage 6. Service, sillcock, and hose bibb valves must be identified, as must any valve installed away from the fixture it serves 7.
Water-hammer arrestors conforming to ASSE 1010 are required wherever quick-closing valves are installed, per IPC §604.9. Dishwashers, washing machines, and irrigation solenoid valves all trigger this requirement 8.
Troubleshooting a stuck or leaking valve
You've found the valve and turned the handle — but the water's still running, or something else went wrong. Most of these problems have straightforward fixes.
The valve won't budge. Gate valves that haven't been turned in years seize up. Don't force the handle — you can snap the stem and turn a small job into a flood. Spray penetrating oil where the stem enters the valve body, let it soak 10 to 15 minutes, then work the handle gently back and forth. If it still won't move, call a plumber before you break it.
Water keeps flowing after you've closed the valve. On an old gate valve this usually means the internal gate has corroded or detached from the stem. On a ball valve, debris may be lodged in the seat — cycle it open and closed a few times to flush it. If neither works, the valve needs replacing.
The handle spins without stopping. That's a stripped stem or a broken gate. You have no reliable shutoff until it's replaced — treat it as urgent.
The valve weeps from the stem. A few drips from the packing nut on an old valve are normal once you move it. Tighten the packing nut a quarter turn at a time until the drip stops. If that doesn't do it, you can try removing the nut, wiping everything down, and reseating it properly — one homeowner reported that stopped their leak 9. If it keeps weeping, the packing is worn out and the valve should be rebuilt or replaced. Experienced plumbers often recommend just replacing an old, corroded valve to avoid future problems 9.
You can't find the shutoff at all. In older homes and condos it may hide behind a removable panel or in a shared space. If you've checked the garage, basement, crawlspace, and water heater and come up empty, call your water utility — they can locate the curb stop and often help identify your interior valve.
When you do replace a shutoff, a ball valve is the better long-term choice. Push-fit valves like SharkBite get a bad rap, but they hold up — experienced plumbers note they can last well over 10 years without issues 10. Replacing a corroded main valve still means shutting the water off at the street first, and if that's not something you can do confidently, this is a job for a licensed plumber.
Maintaining your shut-off valve
A valve that sits untouched for years is a valve that fails when you finally need it. Exercise your main shutoff twice a year — turn it fully off and back on. A ball valve takes one quarter turn; a gate valve needs a few full rotations. If it feels stiff, work it gently rather than forcing it. This keeps corrosion from locking it up and lets you catch a weeping stem early.
While you're there, clear anything blocking access and confirm the label is still readable. A few drops of oil on the handle once a year helps a gate valve from sticking.
Heading away for more than a day or two? Shut off the main valve before you go. A small leak you'd catch at home becomes a major one when no one's there, and in cold weather, draining the lines as well protects against a freeze-and-burst while the house is empty.
Frequently asked questions
Why can't I find my main shutoff valve? Check the basement, crawlspace, garage, or utility closet first. On a slab, look near the water heater or behind a wall panel. In warmer climates it may be outside in an underground box near the street. If you still can't find it, your water utility can help track it down.
What if my shutoff valve is stuck or won't turn? Old gate valves seize. Don't force it — spray penetrating oil on the stem, wait 10 minutes, and use steady pressure rather than a sudden jerk. If it still won't budge, stop and call a pro. Forcing a corroded valve can break it and leave you with no way to stop the water.
Can I install a new shutoff valve myself? If you're comfortable with basic plumbing, yes. Ball valves are the best choice for reliability. Replacing a main valve means shutting the water off at the street first. When in doubt, hire a licensed plumber — a botched valve install can flood your home.
How often should I exercise my main shutoff valve? Twice a year. Turn it off and back on fully to keep it from seizing. Pair it with another twice-yearly habit, like changing smoke detector batteries, so you don't forget.
Do I need a separate shutoff valve after the meter? Yes. The valve before the meter belongs to the city; the one after is yours. If you don't have one, install a ball valve — it's your emergency control without touching city property.
Can I use the city's valve at the street instead? Only in a genuine emergency, and only if you have the right curb key. The city's valve isn't built for routine use and you could be liable for damage. Use your own valve inside whenever possible.