The main water shut‑off valve is almost always near where the water line first enters your home and before it reaches the water heater or branches to fixtures.

Most common places to look

Try these spots in order:

  1. Basement
    • On the wall facing the street, where the main pipe comes through the concrete or foundation.
 * Often near the water heater or a utility area.
  1. Crawl space
    • On the front wall of the crawl space where the main line runs in, sometimes near or directly below the water heater location.
  1. Slab foundation / no basement
    • In a mechanical or utility room with the water heater or furnace.
 * Under the kitchen sink in some slab homes.
  1. Near the water meter or outside
    • On the house side of the water meter, where the pipe enters the foundation or wall.
 * In warm climates, sometimes on an exterior wall near an outdoor faucet or in a ground box by the street or sidewalk.

What the valve looks like

  • You’ll see a main pipe coming in from outside, then:
    • A round “wheel” (gate valve) you turn several times clockwise to close, or
    • A lever handle (ball valve) you turn a quarter‑turn so it’s crosswise to the pipe to shut off.

Quick step‑by‑step to find it

  1. Stand outside and see which side of your house faces the street; that’s usually where the service line comes in.
  1. Go inside to that side of the house and check: basement wall, utility room, or under the kitchen sink, starting near the water heater.
  1. If you don’t see it inside, look outside near the water meter, exterior wall, or a ground box labeled “water” close to the curb.

Safety and emergency tips

  • In an active leak, turn the handle clockwise (round) or 90° to perpendicular (lever) and then check if water stops at faucets to confirm it’s the right valve.
  • If the valve is stuck, corroded, or leaking around the stem, do not force it; call a licensed plumber or your water utility so you don’t snap the pipe.
  • Once you find it, label it clearly and show everyone in the house where it is.

If you describe your home (basement or slab, region/climate, age of house), I can narrow down the most likely exact spot and how to reach it safely.

Information gathered from public forums or data available on the internet and portrayed here.