Water meter moving when the taps are off
A water meter that continues recording while the taps are off may indicate another outlet still using water, an unnoticed filling cycle or a leak. It does not tell you the leak location by itself. Confirm what is being measured and rule out ordinary use before assuming a pipe under the house has failed.
Loyal Plumbers · Updated
Get help with this problemTaps off does not always mean all water use has stopped
A toilet cistern may be refilling, an appliance may be in a cycle or another occupant may be using a fitting. Irrigation, a water treatment device or equipment in a business can also make the apparent quiet period misleading. Record the circumstances rather than relying on a quick glance at the meter.
In a flat or divided property, establish that the meter belongs to the supply you are assessing. A shared arrangement can include use outside your room or home. If the identifier or account information is unclear, ask the supplier or managing agent before interpreting the reading as evidence against a particular pipe or occupier.
Make observations that can be compared
If the meter is normally accessible without risk, note the reading and time while ordinary water use is stopped and cisterns have finished filling. Follow the supplier’s instructions for reading that meter. Do not enter a chamber, remove a sealed fitting or reach into standing water to obtain a reading.
A second reading under comparable conditions can help show whether consumption continued. Smart-meter account data may be displayed over a different interval from an immediate physical observation. Tell the supplier which information you are looking at, rather than treating a historical graph as proof of current flow at that exact moment.
Look for water use that leaves no obvious puddle
A toilet can pass water into the bowl without creating an external leak. A storage cistern or other fitting may discharge through a route that is not visible from the room. Listen for continued filling and note any existing visible drips, but do not remove covers or climb into an unsafe space to investigate.
Tell the plumber if your bill changed suddenly, if a supplier contacted you about continuous use or if the pattern appeared after work. A new high reading may have an explanation other than a buried pipe. Identifying the actual use is more productive than choosing an expensive tracing method before accessible causes are considered.
What an inside stop-valve check can suggest
Thames Water’s leakage code describes comparing meter readings with the inside stop valve closed to help investigate a supply-pipe leak. This relies on knowing the correct valve and meter and on the valve actually isolating the intended supply. If the valve is seized, damaged, communal or uncertain, ask for professional help rather than forcing it.
Movement with a correctly isolated internal supply can point towards water leaving the metered section before that valve. It is not a universal location test: additional branches, shared use or a valve that does not seal can change the interpretation. Give the supplier or plumber the complete observations and conditions, not just the conclusion that it must be underground.
A meter observation cannot clear every plumbing system
A still meter during one observation does not rule out an intermittent leak or water escaping from storage. A closed heating circuit can lose water without continuous movement at the incoming-water meter. If you also see dampness or falling heating pressure, those symptoms need to be assessed in their own context.
Likewise, a moving indicator does not measure the condition of a waste pipe or establish why a ceiling is wet. Investigations should distinguish supply consumption from other water routes. The useful next step is the one that answers the remaining question, rather than treating the meter as a complete plumbing diagnostic tool.
Who to contact and what documents to keep
Contact your water supplier if the observations suggest a supply-pipe issue, unclear meter identification or a billing problem. Their responsibilities and any assistance or leakage allowance depend on the arrangement and current policy. Do not assume that the supplier will repair every private pipe or reimburse every charge.
Keep dated readings, the conditions when they were taken and any correspondence. If a repair is carried out, retain the description and completion date so you can ask about any relevant allowance. A plumber can report findings about the pipework; the supplier remains the appropriate party for meter-account and billing decisions.
When to arrange a leak investigation
If unexplained use continues after accessible sources are considered, a targeted investigation may be appropriate. Acoustic methods can sometimes help on suitable pressurised pipework, but technique selection depends on the pipe, route and evidence. Access and the limitations of each method should be agreed before a survey.
Loyal Plumbers investigates water loss across London and inside the M25 with 10 active vans and a 24/7 service. Use the enquiry form to describe the readings, property and supplier advice. Mention any photographs or account records you can share later by email. Active flooding requires urgent containment rather than waiting to collect a longer history.
Questions we get asked
- Is the meter definitely faulty if no leak is visible?
- No. Water may be passing through a toilet, hidden outlet or concealed pipe. Meter identification, ordinary use and the supply arrangement should be checked before deciding the instrument is at fault.
- Does closing the stopcock locate the leak exactly?
- No. It can help distinguish parts of a known supply arrangement, provided the correct valve works. It does not identify the exact defect or resolve shared branches and unknown pipe routes.
- Can I claim back the extra water charge?
- Ask your supplier about its current leakage allowance conditions and evidence requirements. Eligibility is not automatic, and a plumbing visit cannot promise a billing adjustment.
- Could this be related to low boiler pressure?
- They can be separate observations. Heating-system water loss needs its own assessment; a meter test is not a complete check of a closed heating circuit.
Sources and further reading
Need help with this in London?
Emergency repairs, investigations and planned installations across London and inside the M25. Tell us what you need so we can agree the next step.
Discuss your job