A water meter that moves when no water is being used may mean water is escaping somewhere, such as from a leak on the supply pipe or inside the property. It can also be caused by a toilet that keeps running, a tank or appliance refilling, or a tap that has been left slightly open, so it does not always mean there is a hidden leak.
A few simple checks can help narrow down what is happening. They will not pinpoint a leak, but they can show whether it is worth looking further.
Make Sure Nothing Is Using Water
Before assuming there is a leak, check that all taps are fully off and that no appliances are filling, such as a washing machine, dishwasher or water softener. Toilets are worth checking too. A cistern that keeps trickling into the pan can use water all day without being obvious.
Some homes have a cold water tank in the loft that refills after water is used. The meter may keep moving for a short time while it refills, even though nothing seems to be on.
Check Again Over Time
Once everything is off, take a meter reading and check it again after a period of time. Water company guidance, such as from Wessex Water, suggests waiting 30 minutes to an hour. If the reading has gone up, water is passing through the meter somewhere.
Watch out for anyone in the home using water during the test, as this can give a misleading result. Running the check when the house is quiet, such as late in the evening, can make it easier.
Inside or Outside the Property?
Water suppliers may suggest closing the internal stopcock and checking whether the meter stops. If it stops, the water may be going somewhere inside the property. If it keeps moving with the stopcock fully closed, the leak may be on the supply pipe between the meter and the building, or the stopcock may not be closing fully.
This is only a guide. If the stopcock is stiff, do not force it. A meter that keeps moving can sometimes be a meter issue, which your water supplier can advise on.
What a Moving Meter Does Not Tell You
A moving meter can show that water is being used, but not where it is going. A leak could be under a floor, in a wall, in a loft or underground outside. Water can also travel a long way before it shows, so damp in one place does not always mean the leak is right there.
If you cannot find an obvious cause, our page on finding the source of a water leak explains how an uncertain leak can be narrowed down and investigated.
If your meter is moving and you cannot work out why, a plumber can go through your checks with you and explain the next step.