Why Does Bathroom Sink Drain Gurgles?

Do you hear a gurgling sound when your bathroom sink drains? Ever wonder what’s causing it?

Do you want to fix the problem and stop the sound? Then you’re at the right place.

In this article, we’ll talk about all the possible reasons for the gurgling sound in your bathroom sink and what you can do about it.

What Causes the Gurgling Sounds?

Your bathroom sink makes a gurgling sound due to the presence of air in in your drain. This air escaping from the drain is not supposed to be there to begin with.

When the air inside the pipes can’t escape and ends up putting pressure on the draining water, it makes a gurgling sound.

Due to the blockage caused by air in the passage, the air pressure and obstruction of the path can lead to suction in the drain.

It also pulls the water moving in the P-trap, causing it to make gurgling sounds. The water also has to put more pressure to deal with the obstruction, which leads to further noise.  

The reasons for this gurgling sound in your bathroom sink can be many.

However, the common cause includes the accumulation of stuff like hair or greases in the drain.

They form a clog in the pipeline and create obstructions. Keep reading to learn more!

Blockage in the Drain

The main cause of your bathroom sink gurgle is the partial or complete clogging in the drain.

Both types of blockages are different and show different signs.

Partially Blocked Drain

A partially clogged drain is often the beginning of the complete blockage.

When a drain is partially blocked, the water drains out slowly and you’ll notice gurgling sounds in your sink.

When you notice any signs of partial blockage, make sure you clean your drains immediately. Consider using a good-quality drain cleaner for best results.

Completely Blocked Drain

Partially blocked drains often face complete blockage if not dealt with timely.

When complete clogging happens, you will notice the rising of water in your bathroom sink as it will fail to drain out.

There are several causes of the complete blockage of drains, which include accumulation of hair, soap residue, dirt, toilet paper, oils, or other materials.

When this happens, make sure you check whether the issue is singular or all your drains are showing the same behavior.

If yes, then you’ll need the help of a professional to repair or replace your drainage system.

Sewer Line Blockage

The sewer line is responsible for carrying all the wastewater from multiple drains in your house to discard the in the sewer line of your neighborhood.

In the case that there is a blockage in your sewer line, it will cause all your drains to get clogged and make gurgling sounds.

All the wastewater will fail to be discarded and will accumulate in your sinks and other places.  

The blockage in the sewer line is often caused due to obstructions in the main line, such as bathroom products, tree roots and branches, and broken pipes.

Tree roots often grow into the sewage lines in search of nutrient-rich water.

This can cause blockage and lead to permanent damage to your draining system. 

Bathroom products are another common cause of this blockage.

If you flush out hygiene products, plastics, and paper in your toilet, it can cause serious damage to your drainage system in the long run. 

Vent System Blockage

The vents are an important part of the overall plumbing system as they allow the air to pass without pressuring the water flow.

These vents are connected to all the fixtures in the house and release through the roof.

The vent system puts the air behind the water.  If the vent pipe becomes blocked by debris, leaves, or bird nests, the drainage system will fail.

The gurgling of your sinks is one of the indicators of this issue.

If you notice this sound and also observe the slow drainage of water, then there is a significant possibility of blockage in your vent system. Check the roof vent for obstructions and clear them. 

Bad smells in the drain are also another sign of this issue.   

Air Admittance Valve Issues

Air admittance valves (AAVs) serve as an alternative to traditional plumbing vents. They allow air to enter your drain system to facilitate the flow of wastewater while preventing sewer gases from entering your home.

If your AAV is malfunctioning or poorly installed, it can cause gurgling noises in your bathroom sink. Inspecting and repairing or replacing the AAV can help eliminate the gurgling sound.

Blockage in P-Trap Pipe

Blockage in P-Trap is another common cause of the gurgling sounds that you hear in your bathroom sink.

This small pipe is installed under the sink; it has a curved shape and you’ll easily notice it.

The P-trap is responsible for preventing the sewer gas and drain from coming back up into your drain and sink.

The P-trap protects your bathroom from sewage smells and the backlog of drainage. If the water in the P-trap evaporates or leaks out, air can enter the drain, causing gurgling sounds.

Ensure that the P-trap is properly installed and has enough water to maintain its seal. If you suspect a leak, reach out to a professional plumber for assistance.

When this pipe is damaged or blocked, it can no longer perform its functions appropriately.

Not Enough Vents

Your bathroom sink may also be making the gurgling sounds because of an inefficient venting system.

If you have moved into a new place and you notice this issue from the beginning, then we highly recommend getting your venting system checked by a professional.

Often, these systems don’t have enough vents and that prevents them from functioning satisfactorily.

If your sink makes gurgling noise and your drain takes much longer to drain out the water, then the venting system could be the issue.

Make sure you get it checked and repaired as soon as possible to prevent any further damage.  

Why is the Gurgle Problematic?

If you notice a gurgling sound in your bathroom sink, it may not feel like a big deal.

However, if this issue isnt looked into and fixed immediately, it can cause much bigger problems down the line.

The gurgle is a sign of blockage due to air pressure in your pipes, and it can lead to further clogging due to the accumulation of debris.

The more debris that accumulates, the more blockage it would cause.

Eventually, it will lead to complete jamming of the drain and the failure of the drainage system entirely.

That is why early intervention is the best way to deal with this. Consider seeking a professional’s help to determine the extent of the problem and get it solved.

How to Fix the Gurgling of my Bathroom Sink?

It is not only possible to fix the gurgling sound but it is also not very complicated.

You can get started on your own with two simple steps below:

Plunge and Clean Your Sink

The first step is to plunge your sink to get rid of any obstructions in its ventilation system.

Before you start, make sure to cover the overflow hole with a wet cloth. Place the plunger over the drain and move it up and down with a good amount of pressure.

This will help to dislodge clogs and allow water to flow more freely.

Unclog with a Drain Snake and Auger

A drain snake is an excellent tool to tackle more stubborn clogs. It can reach deeper into the drainpipe to remove blockages.

Push the drain snake down the drain until you feel resistance. Twist and maneuver to break up the clog and pull it out. If a drain snake doesn’t work, opt for a plumbing auger.

It is an even better tool that can reach further and break through tougher blockages, always use caution when using these tools as you don’t want to damage your pipes.

Use Chemical and Natural Drain Cleaners

Chemical drain cleaners are effective in breaking down clogs, but they can also be harsh on your pipes. To use them, carefully follow the instructions on the package.

For a more natural alternative, you can use a mixture of baking soda and white vinegar. Start by adding 1/4-cup of baking soda down the drain and then pour 1 1/4 cup of white vinegar in. Allow it to sit for a few minutes before flushing the drain with hot water.

Clear the Air Admittance Valve

A poorly functioning air admittance valve can cause sink gurgling. Check the air admittance valve; it should be fitted at least 3.5 feet away from the lower trap. If it’s clogged, clean it using a brush to remove any debris. Make sure to reinstall it properly to ensure better airflow within the drainpipe.

Fix P-Trap Issues

The P-trap is designed to prevent toxic sewer gases from entering your home. A clogged or empty P-trap can cause your sink to gurgle. To fix this, pour a bucket of water down the drain to refill the P-trap.

To clear the pipe more thoroughly, you can dismantle the P-trap pipe to clean it out and fit it back again.

If the issue persists, it might be a good idea to call a professional plumber for further assistance.

Clean the Venting System

After cleaning the sink, you need to make sure that your venting system is also clear to prevent any further issues.

Sometimes the opening of the vent on the roof allows material to accumulate and form obstructions in the vents.

Make sure you clean them all out. Check out for any animals that may have nested in your vent and remove them.

When to Call a Professional

While dealing with a gurgling bathroom sink drain can be frustrating, sometimes it’s necessary to call a professional plumber. Here are some signs indicating when to do so, along with the importance of safety and expertise.

Signs of Serious Plumbing Issues

Some signs that your gurgling bathroom sink drain might require professional assistance include:

  • Persistent gurgling despite your preliminary efforts to fix it
  • Slow drainage from the sink
  • Unpleasant odors coming from the drain
  • Water returning to the sink or tub

These symptoms could indicate issues like sewer line clogs, venting problems, or a partial clog that could escalate into a plumbing emergency if not addressed promptly.

Safety Concerns

Calling a professional plumber ensures that your safety concerns are prioritized. Dealing with plumbing issues can be hazardous due to:

  • Exposure to harmful bacteria and substances
  • Potential accidents due to unfamiliarity with tools
  • Risk of damaging pipes or worsening the problem

A professional plumber will have the right tools, protective gear, and experience to deal with the issue safely and efficiently.


A professional plumber possesses the expertise needed to accurately diagnose and resolve the cause of your gurgling sink. Their experience allows them to quickly identify potential root issues and provide the best solutions to prevent future problems.

In addition, their knowledge of local plumbing codes and regulations means they will assure the work is done correctly and legally.

In conclusion, don’t hesitate to call a professional plumber if you notice any serious plumbing issues or if you’re concerned about the safety and execution of a DIY repair.

Schedule an appointment with a local plumber to save yourself time, money, and headache, and to ensure a lasting solution to your gurgling bathroom sink drain.

Preventing Gurgling Bathroom Sink

Regular Maintenance

To prevent your bathroom sink drain from gurgling, it’s important to perform regular maintenance. One easy way to do this is by using a simple mixture of baking soda and vinegar.

These natural ingredients help break down soap scum and other debris that can cause clogs, leading to gurgling noises. Here’s how to do it:

  • Pour 1/2 cup of baking soda down the drain.
  • Follow with 1 cup of white vinegar.
  • Let the mixture sit for 15-30 minutes.
  • Rinse the drain with hot water.

Doing this once a month will keep your drain running smoothly and minimize the chances of encountering gurgling sounds.

Proper Drain Usage

Another crucial aspect of preventing gurgling bathroom sinks is to practice proper drain usage.

Being careful with what goes down your sink drain can reduce the buildup of debris and clogs. Follow these simple plumbing tips:

  • Avoid pouring grease, oil, or any other fatty substances down the drain, as they can solidify and cause clogs.
  • Use a drain strainer to catch hair, soap scum, and other debris that might otherwise enter your drain.
  • Don’t allow large items or excessive amounts of food to go down the sink, even if you have a garbage disposal.

By taking these preventative measures, you can greatly reduce the chances of your bathroom sink drain gurgling, keeping your plumbing system in top condition.

Frequently Asked Questions

What causes a sink to gurgle when draining?

The gurgling noise in your sink usually occurs due to air escaping from the drain or a partial clog in the pipe.

When there is insufficient air inside the pipes, it can prevent the smooth flow of water and create a gurgling sound as the air and water interact in the drain’s P-trap.

How can I stop my bathroom sink from making gurgling noises?

To stop the gurgling noise, try the following:

  • Clear out any debris or partial clogs in your sink using a plumbing snake or plunger.
  • Inspect your plumbing vents for blockages that may be preventing the free flow of air.
  • Check your sink vent installation and make sure it is installed correctly.

Are gurgling sounds from a sink indicative of potential problems?

Gurgling sounds may indicate a partial clog, vent issue, or air pressure problems in your plumbing system. These issues may not be severe initially but, if left unchecked, can develop into more serious plumbing problems.

What home remedies can help with a gurgling sink?

A popular home remedy involves using vinegar and baking soda to clean the P-trap:

  1. Pour 1 cup of baking soda down the drain.
  2. Follow it up with 1 cup of white vinegar.
  3. Allow the mixture to sit for about 10-15 minutes.
  4. Flush the drain with hot water.

Do I need a professional to fix a gurgling sink?

While some gurgling sink issues can be resolved using home remedies or by clearing out debris, more persistent or complex problems may require help from a professional plumber.

For example, if the issue is related to an improperly installed vent or air admittance valve, you’ll need a professional’s expertise.

Can Drano be used to resolve gurgling issues in a sink?

Drain cleaners like Drano can help break down clogs in your sink and alleviate gurgling sounds.

However, solvents like these should be used with caution – they must always be applied according to the manufacturer’s instructions to prevent any damage to your pipes.

Final Thoughts

Bathroom sinks gurgle due to air pressure and obstructions in the vents and plumbing system.

Make sure you get this issue immediately to prevent any damage to your drainage system.

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