Where to look for the main shutoff
Where the valve sits depends mostly on climate and foundation, because the water line comes in below the frost line.
| House type | Where to look |
|---|---|
| Basement | On the wall facing the street, near the water meter, where the pipe comes through the foundation |
| Crawl space | Just inside the crawl space access, on the street side; sometimes a second valve in a closet above |
| Slab on grade | In the garage near the water heater, in a utility closet, or outside where the pipe rises from the ground |
| Condo or apartment | A valve for the unit under a sink, behind an access panel or near the water heater; the building's main is managed by the building |
Many houses also have a pressure regulator right after the main valve, a bell-shaped brass fitting. The diagram below shows the usual order of parts from the street inward.
How to close it: gate valve or ball valve
| Valve | How it looks | To close | Common trouble |
|---|---|---|---|
| Gate valve | Round wheel handle on a stem | Clockwise, many turns | Seizes after years unused; the gate can break off inside; drips at the stem |
| Ball valve | Straight lever handle | Quarter turn, lever across the pipe | Rarely; the lever can be stiff |
| Curb stop | Valve in the meter box, often under a lid | Quarter turn with a meter key | Belongs to the utility in many places; ask before using it |
When the main valve is stuck
A gate valve that hasn't moved in years can refuse to turn. Firm hand pressure is fine; a long wrench or a pipe on the handle isn't, because a broken stem or a gate that snaps off inside can leave you with a leaking valve you can't close at all. If it won't turn, call the utility to close the curb stop, and have the valve replaced once the emergency is over. If a stuck valve closed but now drips from its stem, a gentle quarter turn on the packing nut under the handle often stops it.
Replacing the main shutoff
Replacement means the utility closing the curb stop, cutting out the old valve and installing a new full-port ball valve, often at the same visit as a new pressure regulator or expansion tank. Fixr's January 2025 figures:
| Job | National range |
|---|---|
| Repairing a leaking or damaged shutoff | $150–$300 |
| Replacing the handle only | $150–$750 |
| Replacing the main shut-off valve | $250–$1,000 |
| Replacing a pressure regulator | $250–$1,000 |
Source: Fixr, Water Main Repair Cost, updated January 31, 2025. Where static pressure exceeds 80 psi, IPC 2021 §604.8 requires a pressure-reducing valve.
A seized valve discovered during a leak is an emergency; the same valve found during a calm afternoon is a scheduled job. Some plumbing companies answer 24/7 for the first kind and offer same-day or next-day appointments for the second.
Test it twice a year
Close and reopen the main shutoff every spring and fall so it doesn't seize, and hang a tag on it so anyone in the house can find it in the dark. Keep the path to it clear of storage. If the valve turns but water still flows with it closed, it no longer seals and should be replaced before you need it. While you are at it, find the smaller valves too: the stop under each sink and behind each toilet, and the cold-water valve above the water heater. Closing the one nearest a leak keeps the rest of the house in water, which matters when the repair has to wait for morning. For the steps that follow a closed main, see our burst pipe repair and emergency plumber guides, and for a leak on the pipe outside the valve, water line repair.
Shutoff valve questions
Which way do I turn the valve?
A round handle closes clockwise and usually takes several full turns. A lever handle closes with a quarter turn: when it sits across the pipe, the valve is closed; when it lines up with the pipe, it is open.
Should I close the main when I go on vacation?
It is a sensible habit for long trips. Set the water heater to its vacation or pilot setting first, or switch off an electric heater’s breaker, so it doesn’t heat an idle tank.
What if my house has no main shutoff?
Plumbing codes call for a full-open valve where the water service enters the building. If yours is missing or buried, a plumber can add one, usually with the utility closing the curb stop for the work.
Can I replace the shutoff myself?
Only with the curb stop closed, which many utilities want to do themselves, and with the skill to join pipe that stays tight under full pressure. Many jurisdictions also require a permit for replacing valves.
Sources
- Water Main Repair Cost, Fixr, updated January 31, 2025.
- International Plumbing Code 2021, Chapter 6: Water Supply and Distribution (§604.8, §607.3, Table 604.3), International Code Council.
Reviewed September 27, 2026. Found an error? Write to admin@plumbingrepairquotes.com.