Why is My Toilet Overflowing but Not Clogged?

Why is your toilet overflowing but not clogged?  There could be a few reasons why this is happening. 

Let’s explore why and find some fast solutions. 

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Toilet Overflowing but Not Clogged: What to do?

Can a toilet overflow without being clogged? You bet. Why would a toilet overflow on its own? Check out the reasons and solutions below.

Why is My Toilet Overflowing for no Reason?

There are 6 main reasons why a toilet can overflow without being clogged in a way that is easy to remove.  As always, the best toilet auger is the best tool to deal with a shallow or deep toilet clog.  Why is my toilet overflowing for no reason? 

  1. Vent pipe might be clogged 
  1. It IS clogged 
  1. Clog is past the P Trap 
  1. Septic Tank is Full or Malfunctioning 
  1. Waste Line Venting Issues 
  1. Float Needs Adjusting 

Toilet Overflowing but not Clogged: Toilet Overflowing for no Reason 

Why is your toilet overflowing for no reason?  That’s because there IS a reason, but it’s not as obvious as a shallow clog that can be plunged out of your toilet.  You will have to do some deeper investigation to see which one of the 6 options 

Toilet Overflowing for No Reason: Our 6 solutions 

Here are the 6 solution if your toilet is overflowing and a plunger isn’t working. 

Vent Pipe Might be Clogged

Take a look at our post about unclogging your vent pipes HERE.

Your Toilet IS Clogged

Your best bet before going nuclear and thinking this is a super serious problem, is to use a toilet auger to really get into the pipe and clear it out.

Clog is Past the P Trap

A clog past the P Trap won’t usually be solved with a plunger or even an auger, if its deep enough, you will have to hire someone that has a commercial auger. Commercial augers can typically reach twice as far down your pipes than a consumer auger: 50 feet vs 25 feet.

Septic Tan is Full or Malfunctioning

Our best advice is to call in a septic tank specialist and/or a septic company to pump your septic ASAP.

Waste Line Venting Issues

If you are having waste line venting issues, you may not have enough vents or proper vents installed. Or, you may need to unclog your vent pipe from your roof. Read this post to figure it out.

Float Needs Adjusting

Sometimes the float that regulates how much you tank fills with water may need to be adjusted. Adjusting the float is as simple as bending the metal that holds the float downwards. This means that the tank will stops filling sooner.

Toilet Keeps Clogging and Overflowing 

If you can’t stop your toilet overflowing when flushed no matter what you try, it’s time to call in the experts. Give your local plumbing company a call. Ask your neighbors for a reference.

Can a Bad Flapper Cause a Toilet to Overflow? 

Yes a bad flapper could cause toilet overflow.  The flapper fills your toilet bowl rom he main tank when you flush your toilet.  If the flapper was bad, the toilet bowl could keep filling with water until it overflows.


Your toilet overflowing but not clogged can be a result of a few different things and we hope that you can solve your problem using the knowledge above.