How to Fix Gurgling Drain

How to Fix a Gurgling Drain

A gurgling drain means air is being pushed back through your plumbing system — almost always because of a clog or a blocked vent pipe. Here's how to fix it, step by step, for any drain in your home.

Step 1: Identify Which Drain Is Gurgling

First, figure out the scope of the problem:

• One drain gurgles: Localized clog in that drain or its vent
• Multiple drains gurgle: Main sewer line clog or blocked roof vent
• Toilet gurgles when shower runs: Main line or shared drain issue

Step 2: Clear the Clog (Start Here)

In most cases, a clog is the cause. Work through these methods in order:

For sink and shower drains:

1. Plunge with the right plunger — Luigi's Sink Plunger for sinks/tubs
2. Snake the drain — Flexisnake Drain Weasel for hair clogs
3. Use a chemical cleaner — Amazon Basics Drain Cleaner Gel for grease/soap

For toilets:

1. Plunge with a Korky BeehiveMAX Toilet Plunger
2. Use a toilet auger for deeper clogs

For deep or main line clogs:

1. Locate the sewer cleanout (usually outside near the foundation)
2. Feed a 25ft Drain Auger into the cleanout toward the street
3. Rotate clockwise to break up the clog

Step 3: Check the Vent Pipe

If clearing the drain doesn't stop the gurgling, the vent pipe is likely blocked. Signs:

• Drain flows well but still gurgles
• Multiple drains gurgle simultaneously
• Gurgling happens randomly without water running

The vent pipe runs from your drain system up through the roof. Blockages (leaves, bird nests, ice) prevent air from entering the system. Clearing it usually requires getting on the roof — or calling a plumber.

Step 4: Consider an Air Admittance Valve (AAV)

If a drain consistently gurgles due to poor venting and adding a roof vent isn't practical, a plumber can install an Air Admittance Valve (AAV) under the sink. This one-way valve lets air into the drain system without needing a roof vent.

When to Call a Plumber

• Multiple drains gurgle and clearing individual drains doesn't help
• You suspect a blocked roof vent
• The main sewer line auger doesn't clear the blockage
• Sewage is backing up into fixtures

Bottom Line

Fix a gurgling drain by working from simple to complex: plunge first, then snake, then chemical cleaner, then check the main line. If none of that works, the vent pipe is the culprit and you'll likely need a plumber.