What to Do If Your Toilet Blocks

A blocked toilet is stressful, but staying calm and taking the right steps can prevent the situation getting worse. This guide walks you through what to do when your toilet blocks, from immediate actions to knowing when professional help is needed.

Immediate Steps When Your Toilet Blocks

1. Don't Keep Flushing

Your first instinct might be to flush again, but resist this urge. If the toilet is blocked, additional flushing will add more water and risk overflow. One flush attempt is enough to know there's a problem.

2. Stop the Water Rising

If water is rising dangerously high, quickly remove the cistern lid and push down the flapper valve at the bottom to stop more water entering the bowl. Alternatively, turn off the water supply to the toilet if you know where the isolation valve is.

3. Protect the Floor

Lay towels or newspaper around the toilet base in case of overflow. This makes cleanup easier and protects flooring from water damage.

4. Wait a Few Minutes

Sometimes a blockage will clear itself as toilet paper softens. Give it 10-15 minutes before trying anything else.

Using a Plunger

If you have a plunger, it's often effective for simple blockages:

Use a flange plunger (with an extended rubber flap) for toilets—cup plungers are for sinks
Ensure enough water covers the plunger cup—add some if needed
Insert the plunger at an angle to minimize trapped air
Create a seal over the outlet hole
Pump up and down with firm, steady strokes
After 15-20 pumps, pull the plunger away sharply
If the water drains, the blockage has cleared—flush to test

What Not to Do

Don't use chemical drain cleaners: They're often ineffective on toilet blockages and can damage pipes and toilet components
Don't use wire or coat hangers: You risk scratching the porcelain or pushing the blockage further down
Don't pour boiling water: This can crack the porcelain bowl
Don't keep trying if nothing works: You might make things worse

When to Call a Professional

Call for professional help if:

Plunging doesn't clear the blockage after several attempts
Water is overflowing or won't drain at all
There's sewage backing up
Other drains are also affected (indicating a main drain issue)
There's a bad smell even without an obvious blockage
The toilet blocks repeatedly

Preventing Future Blockages

Once cleared, prevent recurrence by:

Only flushing toilet paper—nothing else
Using reasonable amounts of paper
Teaching children what can and can't be flushed
Keeping a plunger accessible
Addressing any recurring slow draining before it becomes a complete blockage