Why Does My Sink Make a Gurgling Noise (Troubleshooting Guide)

On this page

Quick answer
Confirm the symptom
Tools and prep
Step-by-step troubleshooting
Common causes table
Parts matching
When to call a pro
FAQ
Related guides

Quick answer

A gurgling sink usually means a clogged drain or vent. Clear the drain with a plunger or auger, and check the P-trap. If the noise persists, the vent stack may be blocked.

Confirm the symptom

Gurgling sound when water drains
Slow drainage in the sink
Gurgling only in one sink
Gurgling when using other fixtures
Bad odor from the drain

Tools and prep

Plunger
Plumber's auger (snake)
Bucket
Adjustable wrench
Rubber gloves
Vinegar and baking soda
Turn off water supply before starting

Step-by-step troubleshooting

Check for Drain Clog
Do: Use a plunger to try clearing the drain. If that doesn't work, use a plumber's auger.
Observe: Water drains more freely after plunging or augering.
Means: The clog was near the surface and is cleared.
Next: If gurgling continues, move to the next step.
Inspect P-Trap
Do: Place a bucket under the P-trap. Use an adjustable wrench to loosen and remove the trap.
Observe: Debris or buildup is found in the P-trap.
Means: The P-trap was clogged, causing the gurgling.
Next: Clean the P-trap and reinstall it.
Clean P-Trap
Do: Scrub the P-trap with a brush or use a vinegar and baking soda mixture to dissolve buildup.
Observe: P-trap is clean with no visible debris.
Means: The P-trap is now clear.
Next: Reinstall the P-trap and check if gurgling stops.
Check Vent Stack
Do: Go to the roof and inspect the vent stack for blockages like leaves or nests.
Observe: Debris is found in the vent stack.
Means: A blocked vent stack is causing air pressure issues.
Next: Clear the vent stack of debris.
Test Drainage
Do: Run water in the sink and observe if gurgling stops.
Observe: Water drains smoothly without gurgling.
Means: The issue is resolved.
Next: No further action needed.
Call a Professional
Do: If gurgling persists after these steps, contact a licensed plumber.
Observe: Gurgling continues despite your efforts.
Means: The issue may be deeper in the plumbing system.
Next: End of troubleshooting.

Common causes

Cause	Likelihood	Difficulty	Part often needed
Clogged Drain Hair, soap, or debris can block the drain, causing gurgling as water struggles to flow.	Common	Easy	Plunger, plumber's auger
Clogged P-Trap The P-trap under the sink can accumulate debris, disrupting water flow and causing gurgling.	Common	Easy–Medium	Bucket, wrench, cleaning supplies
Blocked Vent Stack A blocked vent stack prevents proper air flow, causing gurgling due to pressure imbalances.	Sometimes	Medium	Vent cleaning kit
Main Sewer Line Clog A clog in the main sewer line can cause gurgling in multiple fixtures.	Rare	Hard	Professional plumber
Improper Venting Incorrectly installed or missing vent pipes can lead to gurgling due to poor air circulation.	Rare	Hard	Professional plumber
Tree Roots in Pipes Tree roots can infiltrate sewer lines, causing blockages and gurgling sounds.	Rare	Hard	Professional plumber
Low Water Seal in P-Trap If the water seal in the P-trap is low, it can allow sewer gases to enter and cause gurgling.	Sometimes	Easy	Water, P-trap repair

Parts matching

Common parts needed for fixing gurgling sink noises include:

Plunger
Plumber's auger
Bucket
Adjustable wrench
Vent cleaning kit
P-trap repair kit

Ensure you have the correct size and type of parts for your sink model.

When to call a professional

Gurgling persists after clearing the drain and P-trap
Gurgling occurs in multiple fixtures
You find a blockage in the vent stack that you can't clear
You suspect a main sewer line clog
You hear gurgling without any visible clogs

FAQ

Can a clogged garbage disposal cause gurgling?

Yes, a clogged garbage disposal can cause gurgling. Clear the disposal with a wrench or plunger.

Why does my sink gurgle only when the toilet is flushed?

This could indicate a shared vent blockage or a main sewer line issue. Check the vent stack and consider calling a plumber.

Is it normal for a sink to gurgle occasionally?

Occasional gurgling may be normal, but persistent gurgling indicates a clog or vent issue that needs attention.

Can I use chemical drain cleaners for gurgling sinks?

Chemical drain cleaners can help, but they may not clear solid blockages. Use them cautiously and follow the instructions carefully.

How do I prevent future gurgling in my sink?

Regularly clean your drains with baking soda and vinegar, avoid pouring grease down the sink, and ensure proper venting.