If you’re searching for how to unblock slow draining toilet, you’ve probably noticed the water rising slightly higher than normal before slowly disappearing. It’s not fully blocked yet but it’s definitely not flushing the way it should.
A slow draining toilet is usually an early warning sign. Ignore it, and what starts as a minor inconvenience can quickly turn into an overflowing bowl, water damage, or a much bigger drainage problem.
In this guide, we’ll explain why toilets drain slowly, how to unblock slow draining toilet properly, and when it’s time to call in a professional.
Why Is Your Toilet Draining Slowly?
In most cases, a slow draining toilet is caused by a partial blockage. This means something is restricting the flow of water, but not completely stopping it.
The most common cause is a build-up of toilet paper or waste in the toilet trap the curved section of pipe inside the toilet. Even if you’re careful, using too much paper in one flush can start the problem. So-called “flushable” wipes are another major culprit. Despite the label, they don’t break down like toilet paper and often cause blockages.
Over time, waste and debris can also build up further down the pipework. In hard water areas, limescale can narrow the inside of pipes, making it easier for materials to snag and collect. This gradually restricts flow and leads to that slow-draining effect.
Sometimes the issue isn’t inside the toilet itself but further along the drainage system. If you notice other fixtures draining slowly, or hear gurgling noises, there could be a blockage in the main drain line. Tree roots, collapsed pipework, or external drain obstructions can all cause this.
Occasionally, the problem is mechanical rather than a blockage. If the water level in the cistern is too low, the toilet simply won’t flush with enough force to clear waste properly. That weak flush can mimic a blockage.
Understanding the cause is important because it determines whether this is a quick DIY fix or something that needs professional attention.
How to Unblock Slow Draining Toilet
If the toilet isn’t completely blocked, you can often fix the issue yourself. Here are the most effective methods to try.
1. Use a Toilet Plunger
A proper flange plunger (designed specifically for toilets) is your first line of defence.
Ensure there is enough water in the bowl to cover the plunger head
Create a tight seal over the drain hole
Push down gently at first, then plunge firmly 10–15 times
Pull away quickly and check if drainage improves
You may need to repeat the process a few times. If the water level drops more quickly afterward, you’ve likely shifted the blockage.
2. Hot Water and Washing Up Liquid
This method works well for minor organic blockages.
Add a generous squeeze of washing up liquid into the bowl
Leave it to sit for 10–15 minutes
Pour a bucket of hot (not boiling) water from waist height into the bowl
The heat and lubrication can help soften and move the obstruction. Avoid boiling water, as it can crack the porcelain.
3. Use a Toilet Auger
If plunging doesn’t solve the problem, a toilet auger (also known as a plumbing snake) can reach deeper into the trap.
Insert the auger carefully into the toilet bowl
Rotate the handle clockwise
Push gently until you feel resistance
Break up or retrieve the blockage
This tool is particularly useful for stubborn paper clogs or small objects lodged in the trap.
When DIY Isn’t Enough
If you’ve tried these steps and your toilet is still draining slowly, the blockage may be further down the system. A slow drain that keeps returning is often a sign that the issue hasn’t truly been cleared it’s just been temporarily relieved.
If multiple drains in your property are slow, or you notice unpleasant smells or gurgling sounds, the problem could lie in the main drainage line. In these situations, continuing to plunge can sometimes push the blockage further along, making it harder to remove.
A professional plumber has access to specialist equipment such as drain rods, high-pressure water jetting, and CCTV drain inspection cameras. These tools allow them to identify the exact cause of the blockage and fix it properly, rather than just treating the symptoms.
Trying to force a stubborn blockage yourself can also damage the toilet or pipework. Porcelain can crack, seals can loosen, and aggressive chemical drain cleaners can corrode pipes over time.
Why It’s Often Best to Call a Professional
A slow draining toilet might not seem urgent, but it rarely fixes itself. In many cases, it gradually worsens until you’re dealing with a complete blockage or overflow and that’s when it becomes stressful and messy.
Calling a professional early can save you money and prevent damage. An experienced plumber can quickly determine whether the issue is a simple trap blockage or something deeper in the drainage system. They’ll resolve it safely and make sure the problem doesn’t keep coming back.
If your toilet is repeatedly slow, backing up, or showing signs of a bigger drain issue, it’s best not to wait.
Need Help With a Slow Draining Toilet?
If you’ve tried the DIY steps and your toilet still isn’t flushing properly, it’s time to get it sorted properly.
Professional toilet unblocking ensures the issue is fixed at the source not just temporarily eased. Whether it’s a minor obstruction or a deeper drain problem, getting expert help now can prevent a full blockage later.
Don’t wait until it overflows. Get in touch today and have your slow draining toilet cleared quickly and safely.