Toilet Bubbles When Flushed: How to Fix It?

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A fully functioning toilet is definitely a top priority in any house. As we could all agree, toilets are basically the most-used appliance in any household. That’s why our toilets need to run smoothly and without any complications.

However, even the most energy-efficient and modern toilets suffer from basically the same problem as any other toilets – water leakage.

So, what exactly happens to the toilet bowl when you flush it and see toilet bubbles? Let’s find out.

Toilet Bubbles When Flushed

How Toilets Actually Work

The most important thing to know about toilets is that they work on two simple things, force of gravity and water pressure. Now, if you take both of these things away, the toilet will not function at all.

However, if the water pressure is low or barely noticeable, the toilet might start to bubble and lose its power of flushing. And, that’s definitely something that none of us wants.

Basically, when you press the handle the water rushes out of the tank right into the toilet bowl, and that’s how you flush. But, if there isn’t any water in the tank, the toilet won’t be able to work properly.

The water from your dwelling will come into the toilet tank through a little thing called toilet fill valve. And, if something is wrong with the valve, the water can’t get in the tank and that creates a problem.

So, all in all, if the most essential parts of the toilet’s construction are not working properly, you are facing a problem. Now, let’s see how we can help.

Toilet Flushes Slowly and Incompletely

Toilet Bubbles When Flushed: Most Common Reasons

If you see that your toilet is bubbling when you flush, that only means that there is air in a water system inside your toilet. But, how exactly does air come inside the water system of our toilets? Well, there is plenty of ways for air to get into the system.

One of the most common reasons why air gets stuck inside your water system is a poor construction of a water system. You might have bad drain pipes, or overused valves. There are basically a lot different reasons.

Anyhow, the air will rise in your water system until it reaches the highest possible part. That part might be the toilet bowl, or it might be an inside of a tank. This all depends on where the air got stuck in the first place.

That being said, let’s see two most common reasons why our toilet bubbles.

Toilet Flushes Slow but Not Clogged

Fill Valve Malfunction 

As we already mentioned, a bad fill valve just won’t be able to fill the tank with water so it makes a bubbling sound every time it tries to fill it up. It is absolutely important to have a good fill valve, otherwise your toilet won’t work properly.

Anyway, you can check if the fill valve is malfunctioned by removing the cap or the toilet lid. Now, you need to look at the water that sits around the valve and observe whether it makes bubbly noises or not. If the fill valve is bad and it doesn’t do its job properly, you should be able to see and to hear bubbles in the water tank.

Also, it is quite important to know that you don’t want to repair this part all by yourself. Since fill valve is a complicated thing to be installed, you should probably get some professional help. That’s the best possible choice since you can easily break something and create an even bigger mess.

Blockage in the Sewer Line

The blockage inside the sewer line is a really hard and painful thing to deal with. Basically, you can’t do much and all you have to do is sit and wait for professionals to come and fix the problem for you.


However, there is a chance that your toilet bubbles because the blockage is not directly positioned in the sewer. Sometimes, the blockage is not that far away from your toilet. That’s why you need to check this with an auger.

If there’s a clog in your toilet drain, then all you have to do is deal with it properly. On the other hand, there’s nothing you can do if the blockage is located in the sewer line.

Now, you should be able to remove a clog in your bathroom drain with an auger. Namely, all you have to do is to insert an auger inside the toilet drain and push until you hit something hard. Give it a little bit of twirl and pull the clog out from your toilet’s drain.

It is a good idea to turn the water off before you use an auger for this kind of job. By removing water from the toilet, you will actually have a way easier job dealing with the clog.


However, if that doesn’t work, you can always use some unclogging solution product that is specially designed for this kind of stuff.

Here are some helpful articles on unclogging your toilet:

Conclusion: Toilet Bubbles when Flushed

Bubbling toilet is a sign that something is not working properly inside your toilet. That’s why you need to make sure to check every possible option and get the problem fixed as soon as possible.

We have described some of the most common reasons why our toilets bubble when we flush. So it’s up to you now to deal with It. Make sure to get it done properly.