Where is my main water shutoff?

It is usually where the supply enters the house — a basement or crawlspace wall, a utility closet, near the water heater, or in a garage. There is also a street-side valve at the meter.

Last reviewed 2026-07-15

Homes on slabs often have the interior valve in a garage or utility area. Homes in warm climates sometimes have the primary accessible valve outside near the meter box.

Exercise the valve once a year. Valves that have never been turned frequently seize, which turns a leak into a much larger event.

What to check first

  • Where the supply line enters the building
  • Near the water heater and the pressure-reducing valve if fitted
  • The meter box at the street for the utility-side valve
  • That the valve turns fully and reseals without dripping

When to call a professional

  • The valve is seized, leaks when operated, or cannot be located
  • Only the utility-side valve exists and it needs a special key or utility action