The short answer

Start with a flange plunger, which has a fold-out rubber lip. A flat sink plunger will not seal in a toilet because its shape is wrong. Give it fifteen to twenty firm, steady strokes, then try a flush.

If that fails, pour in hot water with washing-up liquid. The water softens the blockage, and the soap helps it slide. Next, try a toilet auger. If the water still will not drain, stop and read the last section of this guide, because the fault may lie further along the pipe.

The plunger method, done properly

Most toilet blockages sit in the trap. That is the S-shaped bend just below the pan. Because a flange plunger is built to seal against that shape, it works far better than a flat cup.

If the bowl is nearly full, bail some water out first. The plunger needs to sit under water, but you do not want a flood. Push the flange into the outlet and press down firmly. Then pull up sharply. The pull matters as much as the push, because the suction on the way back is what dislodges most blockages.

After fifteen or twenty strokes, flush once. If the water moves, you are through. However, if the level barely changes, move on to the next method rather than plunging for ever. For a pan that drains slowly rather than not at all, how to clear a slow draining toilet covers the gentler fixes.

Hot water and washing-up liquid

A soft blockage, such as built-up tissue, often gives way to hot water and soap. Use water that is hot to the touch but not boiling. Avoid boiling water because it can crack a cold ceramic pan, especially in the older toilets found in many North London Victorian terraces.

Add a good squirt of washing-up liquid to a bucket of hot water. Pour it in from waist height, since a little force helps. Then leave it for ten to fifteen minutes before you flush. This will not shift a solid object. For a soft blockage, though, it is often enough on its own, and it makes a second plunge much more effective.

Using a toilet auger

A toilet auger is also called a closet auger or toilet snake. It has a bend that protects the porcelain while it reaches further into the trap than a plunger can. Feed the cable in gently until you meet resistance. Then turn the handle clockwise while you ease it forward.

The turning end either breaks the blockage up or hooks onto it. Draw it back slowly rather than yanking, because a sudden pull can drop the blockage back in, and keep a bucket ready for whatever comes out. If the cable hits something solid that will not give, the obstruction is probably beyond the trap. No home method will reach it. Our guide to unblocking a toilet goes through more cases like this.

What not to do: chemical cleaners in a full pan

A chemical cleaner poured into a full toilet does very little because the product sits on top of the standing water instead of reaching the blockage. Some of these products also give off heat that can crack porcelain, and over time they attack the rubber seals in the cistern. Try the plunger and the hot water first. They are safer and, in most cases, more effective.

When it isn’t really the toilet

Sometimes a toilet blockage is a sign of a blockage further down the shared drain, although the toilet is the first fixture to show it. Watch for these signs:

Other fixtures drain slowly or gurgle when you flush the toilet.
Water rises somewhere unexpected, such as a bath or shower tray, when you flush.
A sewage smell stays after you open a window.

Any of these points away from the trap and towards the main drain run. This is common in Victorian terraces, where several fixtures, or even several homes, share one drain. Our guide to a blocked pipe, branch or main run shows how to tell the two apart. Plunging against a main-run blockage will not clear it, and it can push debris further in. At that point, a blocked toilet clearance visit is the sensible next step. The same advice holds for blocked drains in Barnet as for blocked drains in Wembley, although the cause differs from street to street.

Plenty of homes in Edgware have older pipework. As a result, drain unblocking in Edgware often turns out to be a shared-run problem. For a wider view, read what causes a drain blockage, why drains block so often in North London and our complete guide to clearing a blocked drain. If a Saniflo unit is involved, see why a Saniflo stops flushing. For the main sewer, there is a step-by-step guide to unblocking a sewer pipe. If you want to know what a professional visit may cost, read how much it costs to unblock a drain. Our blocked drains page covers the wider service.

Frequently asked questions

How do I unblock a toilet fast? A flange plunger with a tight seal and firm strokes clears most everyday blockages. However, if it does not, hot water and washing-up liquid left for ten minutes often finishes the job. Flush once afterwards to test it.

What is the best way to unblock a toilet without chemicals? Plunge first, then use hot water and washing-up liquid, then a toilet auger. While all three work on most blockages, they are also gentler on the porcelain and pipework than a caustic cleaner.

Is there a natural way to unblock a toilet? Hot water and washing-up liquid is about as natural as an effective method gets. Bicarbonate of soda and vinegar is milder still. It may help a very minor blockage, but do not rely on it for a stubborn one.

Why does my toilet keep blocking? Usually something is being flushed that should not be, and wet wipes are the most common culprit. However, the cause can also be a build-up further down the drain, or roots in an older shared pipe. If it happens often, send the online enquiry form so someone can look at the drain.