First: stop flushing

A blocked toilet is one of the most stressful plumbing problems — and one of the most common. The good news is that many toilet blockages can be cleared safely at home with a plunger and a bit of patience. This guide walks through the safe DIY steps, what not to do, and when to stop and call a plumber.

If the toilet won’t flush away, do not flush again. A second flush can overflow the pan and flood the floor. Instead:

  1. Lift the cistern lid and check the water level — if it is rising, turn off the isolation valve beside the toilet (usually a small tap on the pipe near the floor).
  2. Put old towels around the base of the toilet and put on rubber gloves.
  3. Give the blockage time — some soft blockages (too much paper) clear on their own within 20–30 minutes as the paper breaks down.

Step 1: Try a plunger

A flange plunger (the type with a smaller cup inside the main cup) works best for toilets. A flat sink plunger is less effective but better than nothing.

  1. Make sure there is enough water in the pan to cover the plunger cup. If the water is very low, add a bucket of water — do not flush.
  2. Place the plunger over the outlet at the bottom of the pan and press down firmly to seal it.
  3. Push and pull with steady, even strokes for 20–30 seconds. Keep the seal — fast, shallow splashing doesn’t work.
  4. Pull the plunger away sharply and see if the water level drops.
  5. Repeat up to 4–5 times. If the water starts to drain, flush once to test.

Patience matters more than force. Gentle, rhythmic plunging clears more blockages than aggressive jabbing.

Step 2: Try hot water and washing-up liquid

If plunging hasn’t worked, this method helps with soft blockages such as paper and waste:

  1. Squirt a generous amount of washing-up liquid into the pan.
  2. Wait 10–15 minutes for it to work down to the blockage.
  3. Pour in a bucket of hot (not boiling) water from waist height. The heat and the height help break up the blockage.
  4. Wait 10–15 minutes, then try the plunger again.

Never use boiling water — it can crack the ceramic pan.

Step 3: Try a toilet auger (drain snake)

A toilet auger is a flexible cable with a crank handle, designed to reach into the toilet trap without scratching the ceramic. It is the right tool if the blockage is deeper than a plunger can reach.

  1. Feed the cable slowly into the outlet, cranking gently as you go.
  2. When you feel resistance, crank and push gently to break up or hook the blockage.
  3. Pull the cable back slowly and clean it. Flush once to test.

Do not force the cable, and do not use a metal coat hanger or a wire — they scratch the glaze and can get stuck, turning a small job into a big one.

What NOT to do

  • Don’t keep flushing. It floods the bathroom.
  • Don’t use boiling water. It can crack the pan.
  • Don’t pour chemical drain cleaner into a toilet. Caustic chemicals can splash back, damage the glaze and seals, and make the job dangerous for anyone who works on the toilet afterwards.
  • Don’t use a wire coat hanger or sharp tools. They scratch the ceramic and can lodge in the trap.
  • Don’t ignore a toilet that keeps blocking. A toilet that blocks every few weeks usually has a deeper problem — a partial drain blockage, a faulty flush, or a problem further down the pipe.

When to call a plumber

Stop the DIY attempts and call a plumber if:

  • The toilet overflows or sewage backs up into the bath, shower, or other drains.
  • More than one fitting is affected (toilet + bath + sink) — that points to a drain blockage, not a toilet blockage.
  • You can smell sewage, or the water level in the pan rises and falls on its own.
  • The toilet blocks again within days of clearing it.
  • You have tried plunging and hot water with no result after a reasonable attempt.
  • The toilet is cracked, loose, or leaking at the base.

A blocked toilet that affects other drains is treated as urgent — call straight away rather than waiting.

Preventing the next blockage

  • Only flush toilet paper and human waste. Never flush wet wipes (even “flushable” ones), sanitary products, cotton buds, nappies, or cotton wool.
  • Don’t use too much toilet paper at once — two smaller flushes beat one overloaded flush.
  • Fix a weak flush promptly. A toilet that doesn’t flush with full force is far more likely to block.
  • If you have young children, a toilet lock can stop toys and wipes going down the pan.

Frequently asked questions

What is the fastest way to unblock a toilet?

A flange plunger used correctly — firm seal, steady rhythm, 20–30 seconds per attempt — clears most soft blockages within a few attempts. Give it time and don’t rush to chemicals.

Can I use drain cleaner in a toilet?

No. Caustic drain cleaners can splash back, damage the pan’s glaze and the seals, and make the toilet unsafe for anyone working on it afterwards. Use a plunger, hot water, or a toilet auger instead.

Why does my toilet keep blocking?

Repeat blockages usually mean a deeper problem: a partial drain blockage, a weak flush, a problem in the soil pipe, or something being flushed that shouldn’t be. If it blocks again within days, get it investigated.

Will a blocked toilet clear on its own?

Sometimes — soft paper blockages can break down within 20–30 minutes. If the water level hasn’t moved after half an hour, or if sewage is backing up elsewhere, don’t wait.

How much does it cost to have a toilet unblocked?

A straightforward toilet unblock is usually a single visit. You get a clear, upfront quote before any work starts — no hidden fees and no surprise call-out charges.

Still blocked? Call Plumb Buster on 07908 948654 — blocked toilets are treated as urgent, and we aim for a same-day visit. See our Toilet Repair in Crawley page.