How to Clear a Clogged Kitchen Sink

What’s Actually Wrong

A slow or fully clogged kitchen sink is almost always grease, food particles, and soap scum building up somewhere between the drain opening and the P-trap under the sink. Grease is the biggest culprit — it goes down as a liquid but cools and hardens inside the pipe, catching everything else that goes down after it. The fix is usually a progression: try the easy, cheap methods first, and only move to taking the pipe apart if those don’t clear it.

How to Unclog a Kitchen Sink: Quick Overview

If you’re looking for how to unclog a kitchen sink, start with the cheap, easy methods first — grease buildup is the most common cause, and it usually clears with hot water, a plunger, or a baking-soda-and-vinegar flush before you ever need a drain snake. If the disposal itself is the problem rather than the drain, see our guide to a garbage disposal that won’t turn on. For a bathroom sink instead, our bathroom sink drain guide covers that separately.

Tools You’ll Need

A sink plunger (a flat-bottomed one works better than a toilet plunger for this), baking soda and white vinegar, a bucket or bowl to catch water, an adjustable wrench, and a flexible drain-cleaning tool or snake for anything the first few steps don’t clear.

Step-by-Step Fix

If you have a garbage disposal, turn it off and check for a reset button on the bottom or side of the unit first — a tripped disposal can look and act exactly like a clog. Run hot water for a minute to soften whatever’s built up, add a squirt of dish soap, then plunge the drain several times with a good seal over the opening. If that doesn’t clear it, pour a cup of baking soda down the drain followed by a cup of white vinegar, cover the drain, let it sit for 30 minutes, then flush with hot water — the reaction helps break up grease and soap residue. Still slow? Place a bucket under the P-trap (the U-shaped pipe under the sink), use an adjustable wrench to loosen the slip nuts on both ends, and remove the trap to clear out whatever’s caught inside, since this is where clogs most often collect. Reattach the trap, hand-tighten the nuts, and run water to check for leaks before calling it done. If the clog is further down the line than the trap, feed a flexible drain snake into the pipe past the trap, twist gently when you feel resistance to grab the clog, and pull it back out.

Watch the Repair

If the plunger and the P-trap have not cleared it, this walkthrough from Ask This Old House shows how the same clog is handled with a snake before anyone calls a plumber.

When to Call a Plumber

If water is backing up into other fixtures (like a nearby dishwasher or a second sink) when you run this one, or a drain snake won’t clear the blockage after a couple of honest attempts, the clog is likely further down the main line and worth having a plumber look at with proper equipment. Avoid chemical drain cleaners if you’ve already tried a plunger or snake on the same clog — the leftover chemical can splash back or make the job more hazardous for whoever works on it next, including a plumber.