Blocked toilet: what to do first, and what makes it worse
Most blocked toilets are one of two problems that need completely different work. Five minutes of checking tells you which one you have.
Do this check before anything else
Run the taps in the bathroom and the kitchen, and flush any other toilet in the property. You are looking for one thing: is anything else draining slowly.
If everything else is fine, the problem is local, in the pan or the branch pipe just beyond it. If the shower is slow, the kitchen sink gurgles or a second toilet is also affected, the toilet is only reporting a problem that lives further down. Clearing the pan in that case achieves nothing.
That distinction decides the whole job, and it takes two minutes.
What makes it worse
- Flushing repeatedly. Each flush adds water that has nowhere to go and brings an overflow closer.
- Chemical drain cleaner. It rarely shifts the obstruction, it can damage older pipework, and it turns standing water into something genuinely hazardous for whoever works on it next.
- Forcing a plunger hard on a partial blockage. This can push material further along to a point that is harder to reach.
- Using other fittings. If the drain below is restricted, the washing machine will find the same exit the toilet did.
What actually causes it
Wet wipes lead by a distance, including the ones sold as flushable. They pass the pan intact and gather at the first bend, then catch everything that follows. Sanitary products and nappies are next, because both swell substantially once wet.
After that: a heavy load of paper in a pan with a weak flush, and objects dropped in accidentally, which is more common than anyone admits.
In converted buildings the soil stack is shared, so one flat’s habits become the whole building’s blockage. If you let property, it is worth saying so explicitly in writing.
When more than one toilet is affected
That is not a coincidence and not a toilet problem. It means the shared stack or the drain below is restricted, which usually makes it a building matter rather than a single flat’s, and that affects who pays. We cover who is responsible for what in this guide.
The right first move is opening the chambers outside, not touching any of the pans.
What we do
Protect the bathroom, establish whether the fault is in the pan or beyond it, clear it with the tool matched to the material, then test with a full flush and check nothing is backing up elsewhere. Removing a pan is a last resort, not a first move.
Fixed £120 plus VAT, no call-out charge at any hour. More on how we handle blocked toilets, or see coverage in Camden, Islington and Hackney.
Area pages with what we typically find nearby: blocked drains in NW1, CCTV drain surveys in Islington and CCTV drain surveys in Camden.