In This Guide
Where is the toilet's water shut-off valve?
Almost every toilet has its own isolation valve on the small flexible pipe that feeds the cistern. Follow that pipe back from where it enters the bottom of the cistern and you will usually find the valve within a few inches, either behind the toilet, beside it, or just below the cistern.
The valve has either a small slotted screw you turn with a flathead screwdriver, or a little lever. When the screw slot or the lever points along the pipe, the water is on. When it sits across the pipe, the water is off.
How to turn off the water to a toilet
- Locate the isolation valve on the supply pipe to the cistern.
- Turn the screw or lever a quarter turn so it sits across the pipe.
- Flush the toilet to empty the cistern.
- Check the cistern does not refill. If it stays empty, the water is off and you can work safely.
That is all it takes for most toilets, and it isolates just the toilet so the rest of your water stays on.
What if there is no isolation valve?
Some older installations have no isolation valve on the toilet. In that case, turn off the water at your home’s main internal stop tap, which is most often under the kitchen sink, in a utility cupboard, or where the supply pipe first enters the property. Turning it clockwise shuts off the cold water to the whole house, so you will lose water everywhere until you turn it back on. Fitting an isolation valve is a quick job for a plumber and well worth doing so you never have to shut off the whole house for a toilet again.
What if the valve is stuck or leaking?
Isolation valves that have not been touched in years can seize up or start to weep once you move them. Do not force a stuck valve, as you can snap it or make a small leak worse. If the valve will not turn, is dripping after you have used it, or the toilet keeps running with the water off, that is the point to call a plumber rather than risk turning a five-minute job into a flood.
For an overflowing or continuously running toilet you cannot stop, our emergency plumbers in London can attend quickly. And if the reason you are shutting the water off is a leak at the toilet, our guide to leaky toilet quick fixes covers the common causes and what to check next.
How 0800 Homefix can help
Most people can turn off a toilet themselves in under a minute, and this guide should get you there. When the valve is seized, the toilet will not stop running, or you would simply rather have it sorted, 0800 Homefix covers London and the South East and can fit an isolation valve, replace a failed one, or fix the underlying fault.
0800 Homefix charges as the first hour of labour, paid in advance, with any parts or further work quoted and agreed with you before it begins. For current rates, see our rates page. Our labour is guaranteed for 12 months, and any parts we fit are covered by the manufacturer’s 12-month guarantee.
Frequently asked questions
Where is the water shut-off for a toilet?
On the flexible supply pipe feeding the cistern, usually within a few inches of where it enters the bottom of the cistern. Look for a small screw or lever valve behind or beneath the toilet.
How do I turn off the water to just my toilet?
Turn the isolation valve on the toilet’s supply pipe a quarter turn so it sits across the pipe, then flush to empty the cistern. This isolates only the toilet and leaves the rest of your water on.
What do I do if my toilet has no isolation valve?
Why won’t my toilet isolation valve turn?
Valves that have not been used for a long time often seize. Do not force it, as it can snap or leak. A plumber can free or replace a stuck valve safely.
Helpful resources
- WaterSafe: find an approved plumber in your area for valve and cistern work.
- Consumer Council for Water: independent advice on household water and plumbing.
Spotted Any of These Warning Signs?
Stuck valve, running toilet, or no isolation valve at all? 0800 Homefix has plumbers across London and the South East who can sort it quickly, seven days a week, 365 days a year.
Editorial note: This article is intended as a general homeowner guide. All plumbing work on supply pipes should be carried out by a qualified, WaterSafe-registered plumber. If you suspect a gas leak, leave the property immediately and call the National Gas Emergency Service on 0800 111 999.
