Short answer
Bail out standing water, then plunge with a cup plunger while you block the other drain (and the disposal, if you have one). If that fails, put a bucket under the P-trap, unscrew the slip nuts and clean the trap by hand. Still stuck? The clog is past the trap: run a hand snake into the trap arm. Skip boiling water on PVC and never plunge or snake a drain with chemical cleaner in it.
Before you start
Figure out where the clog is. If only one bowl of a double sink is slow, the clog is above the point where the two drains meet. If both bowls back up, it is in the shared trap or beyond. If the dishwasher or another fixture backs up too, it is further down the line, and a plunger may only push it around.
What you need
How to unclog a kitchen sink, step by step
Run hot tap water
If the sink still drains slowly, run very hot tap water for a minute or two to soften grease. Use hot tap water, not boiling water, if you have PVC drain pipes or a porcelain sink.
Bail out most of the standing water
Scoop the water into a bucket until an inch or two is left. That leaves enough water for the plunger to push against and less to spill later.
Block the other openings
In a double sink, push a stopper or a wet rag hard into the other drain, or have someone hold it down. If you have a dishwasher, clamp its drain hose or hold a rag over the air gap. Otherwise the pressure escapes the easy way, a point The Home Depot makes too.
Plunge with short, sharp strokes
Center a cup plunger over the drain, make sure the cup is under water, and pump up and down a dozen or more times, keeping the seal. Pull it off sharply on the last stroke. Repeat a few rounds. If the water drops, flush with hot tap water for a minute.
Remove and clean the P-trap
Put a bucket under the trap. Unscrew the two slip nuts by hand (or gently with pliers), lower the J-bend, and empty it. Clear grease and food with a gloved finger or an old brush, rinse it in another sink, check the slip washers, and refit it hand tight plus a little more.
Snake the trap arm
With the trap off, feed a hand snake into the pipe that goes into the wall. When you feel resistance, lock the cable and crank it to bite into the clog, then pull back and repeat. Pull the cable out slowly, wiping it as it comes.
Reassemble and test
Refit the trap, run hot tap water for a few minutes, and check every slip nut for drips with a dry paper towel. Tighten a quarter turn if one weeps.
Why kitchen sinks clog
Fats and oils go down warm and liquid, then cool and stick to the pipe walls. Food scraps, rice, pasta and coffee grounds catch on that layer. Over time the opening shrinks until water backs up. The trap, which holds water by design, is where most of it settles.
- Wipe greasy pans with a paper towel before washing them.
- Keep a mesh strainer in the drain when you are not using a disposal.
- Run hot tap water for a bit after washing up.
When a plunger will not work
If plunging and cleaning the trap do not help, the clog is in the drain line past the wall. A hand snake reaches the first stretch; anything beyond that is a job for a larger drum auger or a plumber. Compare tools in the best drain cleaners and snakes.
What about chemical cleaners?
Caustic gel cleaners can cut through grease, but they are hazardous, they should never be mixed with another product, and they leave you working on a drain full of chemical if they fail. Enzyme cleaners are slower and gentler, better for upkeep than for a sink that has stopped draining. Read the honest take on baking soda and vinegar before you reach for the pantry.
Questions people ask
What is the fastest way to unclog a kitchen sink?
A cup plunger, used with the other drain in a double sink blocked so the pressure goes into the clog instead of out the other side. If a few rounds of plunging do not move it, take the P-trap off and clean it: that is often quicker than plunging longer.
Can I pour boiling water down a kitchen sink?
Not if the drain pipes under the sink are PVC, or if the sink is porcelain or fireclay. Very hot tap water is the safer way to soften grease. Many plumbing guides note PVC is rated for continuous use only up to about 140°F.
How do I unclog a kitchen sink with a garbage disposal?
Turn the disposal off at the switch first. Run it briefly with cold water in case the clog is in the disposal itself, then plunge the other bowl with the disposal side blocked, or plunge the disposal side with the other drain blocked. Never put your hand in a disposal.
How do I unclog a kitchen sink with standing water?
Bail most of the water into a bucket first so you can see and so less spills when you open the trap. Leave an inch or two in the bowl if you plan to plunge: the plunger needs water, not air, to push against the clog.
Does baking soda and vinegar unclog a kitchen sink?
Rarely on its own. The fizz is mostly carbon dioxide and much of the cleaning comes from hot water and leftover baking soda. It is fine as gentle upkeep, but a plunger or cleaning the trap is far more likely to clear a real clog.
When should I call a plumber?
If the trap is clean and a hand snake will not get through, if both sinks or other fixtures back up together, or if water comes up in another drain when you run this one. Those point to a clog further down the line.
Sources
Last reviewed October 12, 2026. Parts, sizes and listings change; check the product details before you buy, and follow the maker’s instructions.