Stopcocks and water meters: who owns what, and using a meter to find a leak

Between the water main in the street and the taps in your kitchen there are usually two valves and, in many homes, a meter. Knowing which is which, and whose job each one is, saves time when something goes wrong. If you need to find your internal stopcock or deal with a leak right now, go to our guide to finding your stopcock and a leak.

This guide follows the Consumer Council for Water (CCW), which covers household water customers in England and Wales. In Scotland and Northern Ireland, the arrangements and responsibilities are set by Scottish Water and NI Water, so check with Scottish Water or NI Water rather than relying on this page.

The layout of a typical supply

From the street to the house, a typical supply in England and Wales runs like this:

1. The water main under the road. CCW says it is owned by your water company, which is responsible for looking after it.
2. The communication pipe from the main to the boundary of your property. Also the water company's.
3. The external stop tap (outside stopcock), usually under a small cover in the pavement or near the boundary. CCW says this is the water company's responsibility.
4. The water meter, if you have one, often in a chamber next to the external stop tap, though some meters are inside the house. CCW says the meter is the water company's too.
5. The supply pipe from the boundary into the house. CCW says the homeowner is responsible for pipes on private property up to the boundary. If the pipe is shared with neighbours, it becomes the joint responsibility of everyone connected to it. In some older homes this pipe is lead; see lead water pipes.
6. The internal stopcock (stop tap, main stop valve), where the supply pipe comes into the house. Yours.
7. Everything after that, from pipes and valves to taps, cisterns and appliances. Also yours.

CCW has an illustrated explanation of who is responsible for which pipes. Older streets, flats and shared supplies can be laid out differently, so if in doubt ask your water company.

The internal stopcock

This is the valve you should use to turn off the water in an emergency. It is yours to use, maintain and replace. Every householder should know where it is and check that it turns. The Water Supply (Water Fittings) Regulations 1999 require a stopvalve on the supply to each separate premises so that its supply can be shut off without shutting off anyone else's. See Schedule 2, paragraph 10.

Our stopcock guide covers where to look, which way to turn it and what to do if it is seized.

The external stop tap

CCW lists the external stop tap as the water company's responsibility. It can be deep below the cover, it may need a special key, and on older streets one valve may control more than one house.

• If you need it turned off, for example because your internal stopcock is seized or the leak is on the supply pipe before it, contact your water company. Its website will give the number to call.
• If it is broken, leaking or buried, report it to your water company.
• Do not dig round it or force it. Damaging it can cut off neighbours too.

If you are not sure whether you can operate it yourself, ask your water company before you try.

The water meter

CCW says the water company owns the meter and is responsible for maintaining it. If you think it is damaged, not working, or giving wrong readings, contact your water company.

Meters vary. Older meters have a row of numbers and small dials. Smart meters send readings to the water company automatically, and CCW says they usually also have a small display you can read directly. Some water companies give access to readings through a website or app.

If you do not have a meter, CCW says you can ask your water company to fit one free of charge. Water companies can also decide to fit smart meters as part of their own programmes.

Using the meter to check for a leak

A meter is the simplest way to check for a hidden leak. CCW's advice on a suspected leak on your supply works like this:

1. Turn off everything that uses water. Taps, the washing machine, the dishwasher, outside taps. Wait for toilet cisterns and any loft cistern to finish filling.
2. Read the meter, or watch it. CCW says the black on white or white on black dials usually show whole cubic metres, and the red dials (or red on white) show fractions of a cubic metre. Movement on the red dials, or a spinning indicator if your meter has one, shows water is passing.
3. Wait and check again. If the reading has moved with nothing running, water is going somewhere.
4. Close the internal stopcock and check once more. If the meter still moves with the stopcock shut, the leak may be on the supply pipe between the meter and the house. If it stops, the leak is probably inside the house.

If your meter is outside, CCW says to check it only if it is safe to do so, and not to try to lift a heavy metal cover. It describes lifting a lighter inspection cover with a screwdriver blade and removing a polystyrene protector, if there is one, to see the meter face, which may be some way down. Smart meter users may see a leak alert from their water company instead. CCW says a fully activated smart meter should let you know if it detects constant water use.

If the meter shows a leak

• Inside the house: look at toilets first, then visible pipework and appliances. See our guides to a running toilet and to finding a leak. CCW says leaks inside the property are the homeowner's responsibility to repair.
• On the supply pipe outside: contact your water company. CCW says some companies offer one-off help to domestic customers with finding and repairing a supply pipe leak, and that conditions vary, so check the company's own policy. It also says that after a repair your company should offer a leakage allowance for the lost water. Ask your water company how its allowance works.

If you have lost water completely, or pressure has dropped suddenly, see low water pressure and check with neighbours before assuming the problem is yours. In a freeze, see our guide to frozen and burst pipes.

Who owns the water meter?

In England and Wales, CCW says the water company owns the meter and is responsible for maintaining it. Contact your water company if you think it is faulty.

Can I turn off the outside stopcock myself?

CCW lists the external stop tap as the water company's responsibility. It can be deep, need a special key and serve more than one house. Ask your water company to operate it, especially in an emergency.

How do I know if I have a leak on my supply pipe?

Turn off all water use, check the meter is still, then close your internal stopcock. If the meter still moves with the stopcock closed, the leak may be on the supply pipe. Contact your water company.