How to fix a toilet that keeps running or filling after flushing
A continuously running toilet is usually caused by a worn inlet or flush valve seal inside the cistern. Over time, debris or limescale prevents the valve from sealing properly, allowing water to flow constantly into the pan. If you are experiencing constant running water into the bowl, a constantly refilling cistern or a hissing or dripping noise after flushing, the following steps can help to resolve the issue:
- Turn off the water supply to the cistern.
- Remove the flush plate, button panel or cistern lid to access the internal parts.
- Check that the inlet float valve moves freely and isn’t catching on anything.
- Inspect the rubber seals at the base of the flush valve — replace if worn, distorted, or dirty.
- Clean away any limescale or debris using white vinegar or mild descaler.
- Reassemble, restore the water supply, and test the flush.
Tip: A small amount of water movement after flushing is normal, but a steady trickle means the valve isn’t sealing properly.
Replacement flush and inlet valve kits are available from our official spares website