Where Is My Stopcock? How to Find It and Turn Your Water Off

If a pipe bursts, the single most useful thing you can do is turn off the water at the stopcock. The trouble is, most people only go looking for it when water's already coming through the ceiling. Take two minutes now and find yours.

Where to look first

Your internal stopcock (also called a stop tap or stop valve) is usually where the mains water pipe enters the house. In order of how often we find them:

1. Under the kitchen sink. By far the most common spot. Look at the back of the cupboard for a tap on a pipe coming up through the floor.
2. Under the stairs. Especially in older terraced and semi-detached houses.
3. In a downstairs toilet or utility room.
4. In the airing cupboard or near the boiler.
5. In the garage, near the front door, or under a floorboard just inside it.
6. In a flat: often in the airing cupboard, kitchen, or a shared cupboard in the corridor.

It'll look like a small tap with a round or T-shaped handle on a copper or plastic pipe. Some newer homes have a lever valve instead.

How to turn it off

• Turn the handle clockwise to close it (righty-tighty).
• Then open the cold tap at the kitchen sink to check the water's stopped and drain the pipe.
• If it's a lever, turn it 90° so it sits across the pipe.

When you turn it back on, open it fully and then give it a quarter-turn back — that helps stop it seizing.

What if it won't turn?

Stopcocks that haven't moved in years often seize. Don't force it with a wrench — you can snap the spindle and turn a small problem into a flood. A drop of penetrating oil and gentle back-and-forth pressure sometimes frees it. If not, it's worth having it replaced before you need it.

The outside stop tap

There's usually a second stop tap outside, under a small metal or plastic cover in the pavement or at the boundary of your property. In Preston and the surrounding area this belongs to United Utilities. It often needs a special long key, and in some cases it's shared with neighbours — so use the internal one if you possibly can.

Also handy: isolation valves

Many taps, toilets and washing machines have their own small isolation valve — a little screw slot on the pipe just below. Turn it a quarter-turn with a flat screwdriver so the slot sits across the pipe, and you can work on that one fitting without turning off the whole house. Very useful for fixing a dripping tap or a running toilet.

Got a leak right now?

Turn off the stopcock, switch off the electrics in the affected area if water is near sockets or lights, then follow our burst pipe guide. Call us on 07949 075721 — we're based in Bamber Bridge and cover Preston and the surrounding areas.

Can't find your stopcock at all? We can locate it, check it works, and replace it if it's seized — a small job that can save a lot of damage later.