How to Unclog a Kitchen Sink Drain

If your kitchen sink drain is stopped up, you need to know how to unclog it. There are several simple, highly effective methods.

Step 1 - Run Some Hot Water

Before proceeding to plunge or snake your kitchen sink, attempt to break up the source of the clog by running a steady stream of very hot water into the drain. This will help dissolve and/or wash away clog-forming grime and grease. If this fails to produce any results after 10 to 15 minutes, you will most likely need to plunge the drain. To prevent future clogs, allow hot water to flow down the drain for several minutes a week, to clear contaminants before they have a chance to present a problem.

Step 2 - Plunge the Sink Drain

If hot water failed to do the trick, you need to plunge the clogged drain. Begin by using a wet rag to stop up the sink's overflow opening or the other drain in a double sink. This ensures that all the force exerted by the plunger is concentrated on the source of the clog. Next, fill the sink with a small amount of water. Firmly position the head of the plunger over the drain and give it a vigorous plunging. With any luck, the hot water from the first step will have provided the clog with some lubrication, enabling it to more easily be driven downward.

If plunging fails to produce any results after half an hour, you need to snake the drain.

Step 3 – Remove the Trap

TIP: Our plumbing consultant Mark Vander Sande suggests, “It is better to remove the trap and tail piece that is attached to the pipe from the wall or the floor and use the hand auger to snake this drain. Trying to get the corkscrewed end of the auger through the basket strainer can get difficult and if the snake gets caught in the pipe you have a large problem.”

Begin this step by placing a bucket beneath the drain trap to catch the water that will flow out when it is removed. Next, use a plumber's wrench to carefully twist off the trap.

If your drain trap is dirty, clean it before proceeding to reattach it. To do this, soak the trap in a mixture of warm water and mild liquid soap, use a hard-bristled scrub brush or an expendable toothbrush to remove any caked-on grime, then rinse the solution off in warm water. If your drain trap is exceptionally filthy or rusted, you should consider replacing it.

TIP: Mark adds, “If the piping under the sink is chrome plated brass and is old, removing the slip joint nuts may cause the piping to break. This is common for older chrome plated piping and traps. It is better to remove them and replace them with pvc piping an traps. If the tailpiece does not come out of the wall or floor, you can cut it flush at the pipe connection and take a small hack saw blade to cut through the brass pipe inside of the larger drain pipe. Just cut through the chrome plated brass and use a screw driver to pry it out once it is cut.”

Step 4 – Snake the Drain

Carefully insert the corkscrewed end of your auger into drain pipe in the wall. Turn the auger's handle clockwise to send the corkscrewed end further down the drain. Continue driving the auger downward until it becomes difficult to turn the handle. This typically means that you have come into contact with the source of the clog. If possible, continue to turn the handle and drive the corkscrewed end of the auger downward until it penetrates and breaks up the source of the clog. Once the clog has been successfully broken up, retract your auger by turning its handle counterclockwise. Reassemble the drain and run some hot water to wash away any remaining pieces of the clog.

Mark Vander Sande, professional plumber, contributed to this article.