Fix a water meter that runs when nothing is on
We'll help you isolate the leak, check toilets and irrigation, and know when to call a plumber.
What you'll need
- Food coloring (for toilet test)
Step-by-step diagnostic
Quick triage — pick your path
Get started
Choose the option that matches what you see. You can jump straight to that section.
- Follow this guide Work through the full procedure from shutting off fixtures to checking sources.
- Isolate the leak You want to determine if the leak is in the house or main line.
- Check toilets The leak is in the house and you want to test toilets.
- When to call a plumber Meter runs with main valve off, or you cannot find the leak.
Show full guide
Steps
Goal: Isolate the leak, check common sources, and fix or call a plumber.
- Shut off all fixtures. Check the meter. If it runs, shut off the main valve. If the meter stops, the leak is in the house.
- Check toilets with food coloring. Check irrigation and hose bibs.
- Good: Found and fixed. Bad: Call a plumber.
Isolate
Goal: Determine if the leak is in the house or the main line.
- Shut off the main valve. If the meter stops, the leak is inside. If it keeps running, the leak is in the main line—call a plumber.
- Good: Leak is in the house. Bad: Main line—call a plumber.
Check toilets
Goal: Find silent toilet leaks.
- Add food coloring to the tank. Wait 15 minutes. If color appears in the bowl, replace the flapper.
- Good: Flapper fixed. Bad: Check irrigation and spigots, or call a plumber.
When to get help
Call a plumber if:
- The meter runs with the main valve off (main line leak).
- You cannot find the leak after checking toilets and irrigation.
Verification
- The meter does not move when all fixtures are off.
- No silent leaks (toilet test shows no color in bowl).
Escalation ladder
Work from the device outward. Stop when the problem is fixed.
- Shut off all fixtures Ensure nothing is using water; check the meter.
- Isolate house vs. main Shut off main valve; if meter stops, leak is in the house.
- Check toilets and irrigation Test toilets with food coloring; check irrigation and spigots.
- Call a plumber Main line leak or cannot find source—call a plumber.
What to capture if you need help
Before calling support or posting for help, have these ready. It speeds everything up.
- Meter movement with fixtures off
- Meter movement with main valve off
- Toilet test results
- Irrigation and spigot condition
- Steps already tried
Does the meter run when all fixtures are off?
Shut off every faucet, toilet, ice maker, humidifier, and irrigation. Wait 5 minutes.
You can change your answer later.
No leak detected
Does the meter stop when you shut off the main valve?
Shutting off the main valve isolates the house from the main line.
Yes (leak in house) No (main line leak)
You can change your answer later.
Did you find the leak (toilet, irrigation, spigot)?
Toilets: food coloring test. Irrigation: shut off and check. Spigots: look for drips.
You can change your answer later.
Call a plumber
Reviewed by Blackbox Atlas
Frequently asked questions
- Why would the water meter run when nothing is on?
- A running meter with no fixtures on means a leak somewhere—toilet flapper, irrigation, outdoor spigot, or a pipe. Toilets are the most common cause of silent leaks. Irrigation systems and hose bibs are also frequent sources.
- Can I find the leak myself?
- Yes. You can shut off the main valve to isolate house vs. main line. You can check toilets with food coloring. You can check irrigation and outdoor spigots. If you cannot find it, a plumber can use leak detection equipment.
- When should I call a plumber?
- Call a plumber if: you shut off all fixtures and the meter still runs, you cannot find the leak, or the leak is in the main line. A plumber can locate and repair the leak.
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