400L/day
Water wasted
£80/month
Added bill cost
£75–£160
Typical repair cost
Frequently Asked Questions
How do I know if my toilet is leaking internally?
Put a few drops of food colouring into the cistern tank. Wait 15 minutes without flushing. If coloured water appears in the toilet bowl, the flush valve is leaking — water is running from the cistern into the pan even when not flushed. This is a silent leak that can waste up to 400 litres per day.
Can a leaking toilet cause ceiling damage?
Yes. If the toilet is on an upper floor and leaking from the pan connector, close-coupling joint, or supply pipe, water can track through the floor and soak into the ceiling below. Damp patches, brown stains, or a soft ceiling are signs of a slow toilet leak from above. Fix the leak immediately and let the ceiling dry before repainting.
Is a leaking toilet an emergency?
If the toilet is running into the pan, it's not an emergency but should be fixed promptly to avoid high water bills. If water is leaking onto the floor or through the ceiling, isolate the water supply at the toilet isolation valve (behind the toilet) and call us for a same-day repair.
How much does it cost to fix a leaking toilet?
Most toilet leak repairs cost between £75 and £160 depending on the cause. Flush valve diaphragm: £75–£100. Fill valve replacement: £90–£140. Pan connector reseal: £120–£160. Close-coupling kit: £95–£130. We always give a fixed price before starting any work.
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