How to Unclog a Sink: Home Methods That Actually Work
updated 11 July 2026
Quick answer
Start with a plunger - block the overflow opening and give it several vigorous strokes so the pressure shifts the clog. If that doesn't work, pour baking soda into the drain, follow it with vinegar, and flush with boiling water after 15 minutes. A stubborn clog most likely sits in the trap - unscrew it, clean it out, and screw it back together.
Step by step
- 1
Remove the standing water and cover the overflow
Scoop out the water standing in the sink with a cup, or soak it up with a cloth, so you can work. If you're unclogging a double sink or a washbasin with an overflow opening, plug that second opening with a wet rag. Without that, the plunger can't build pressure, because air escapes out the side.
- 2
Use a plunger
Position the plunger's rubber cup so it seals tightly around the drain, and leave enough water in the sink to cover the cup. Hold the plunger upright and make a dozen or so vigorous up-and-down strokes without lifting it off the bottom. Finish with a strong pull upward - if the water starts draining, the clog has moved.
- 3
Try baking soda, vinegar, and boiling water
When the plunger isn't enough, pour about half a cup of baking soda into the drain and add roughly the same amount of vinegar. The mixture will start to fizz - leave it for 15 minutes to loosen the grease and buildup. Then slowly pour in a full kettle of boiling water to flush away the dissolved grime.
- 4
Take apart and clean the trap
If the clog sits deeper, place a bowl or bucket under the trap to catch water and debris. Unscrew the trap's nuts by hand (they usually come loose without tools), remove it, and pull out the contents - typically a packed sludge of grease and food scraps. Rinse the parts under running water, clean the inside, and reassemble everything in reverse order, checking the gaskets.
- 5
Push the clog through with a drain snake
For clogs sitting farther down the pipe than the trap, use a drain snake, also called a plumber's auger. Feed its end into the pipe and turn the crank while pushing - the coil will either break through the clog or pull it out. Once past the resistance, flush the pipe with boiling water, and pull the snake out slowly so you don't fling dirt around.
- 6
Check the flow and put everything back
Turn on the warm water and check that it drains freely without backing up. Look under the sink to make sure the trap isn't dripping anywhere after reassembly. If the water still stands despite a cleaned trap, the clog sits deeper in the main stack, and that's when a longer snake or a plumber's help comes in.
What not to do
Don't pour caustic soda granules (sodium hydroxide, NaOH) into a sink that already holds standing water from failed attempts or residue from another product. The substance heats up sharply on contact with water and can spatter, and mixed with acids it gives off fumes. If you do reach for a commercial product, use it on an empty, calm drain and air out the room.
Don't combine different chemical products at once, or one after another without flushing the pipe in between. The reactions between them can be violent, and they still won't clear the pipe any better than mechanical methods. Work in gloves and protect your eyes, especially when water could splash.
Kitchen sink and bathroom basin - different causes
In a kitchen sink, the clog is usually solidified grease mixed with coffee grounds, food scraps, and soap. That's why hot water, baking soda with vinegar, and regular flushing with boiling water work best here - they dissolve the grease before it packs into a plug.
In a bathroom basin, the main culprits are hair and soap scum wrapping around the stopper and the drain inlet. Here, mechanically removing the clog - unscrewing the stopper and pulling the tangle out with pliers or a hook - tends to work better than pouring in chemicals.
How to prevent clogs
Fit a strainer over the drain to catch food scraps and hair, and empty it regularly. Don't pour fat or frying oil down the sink - once they set, they coat the pipe; pour them into a jar and throw it out with the trash.
Every so often, flush the drain with a kettle of boiling water, and every few weeks do a preventive rinse with baking soda and vinegar. That habit removes the thin film of grease before it grows into a hard clog.
Frequently asked questions
›How do I unclog a sink at home without chemicals?
The most effective combination is a plunger plus flooding the drain with baking soda and vinegar. After 15 minutes, flush everything down with boiling water to dissolve the grease. If that doesn't work, clean the trap under the sink by hand.
›What do I do when the sink is clogged and the water won't drain at all?
Remove the standing water, plug the overflow, and work the plunger so the pressure shifts the clog. If the water still stands, unscrew and clean the trap under the sink. A clog sitting deeper in the pipe can be broken through with a drain snake.
›Do baking soda and vinegar really unclog pipes?
They help with grease and fresh, not-too-hard buildup, especially in a kitchen sink. They won't break up a packed tangle of hair or a solid object, though - that takes mechanical cleaning of the trap or a drain snake.
›When should I call a plumber for a clogged sink?
When water still backs up after you've cleaned the trap and used a snake, or when several drains clog at once. That's a sign the blockage sits in the building's main stack, which is hard to reach with home tools.
›Why does a bathroom basin clog more often than a kitchen sink?
A basin mostly collects hair and soap scum, which easily wrap around the stopper and the drain inlet. In a kitchen sink the problem is more often solidified grease. That's why a basin is best cleaned mechanically, by pulling the clog out from under the stopper.