How to Unclog a Drain
Learn how to unclog a kitchen or bathroom drain using things you already have at home. No chemicals, no plumber, no drama.
The first time we dealt with a clogged drain, we panicked and poured an entire bottle of chemical drain cleaner down the sink. It did not work and it smelled terrible, and pouring a bottle into a drain that is not moving is the exact case Poison Control warns about, because the product sits in the pipe and can splash back out.
Turns out there are faster and safer ways to handle it. Most clogs happen in the first few inches of pipe, right below the drain cover. Hair, soap buildup, food scraps, and grease are the usual suspects. You do not need a plumber for any of them.
This guide covers four methods in order of how easy they are. The first one is mostly waiting for a kettle to boil, and it fixes a lot of slow drains on its own. Start there and work your way down only if you need to.
Boiling water from a kettle or pot, or very hot tap water if your drain pipes are old PVC. Baking soda and white vinegar from the kitchen. A pair of needle-nose pliers or a bent wire hanger for pulling out hair clogs. A small bucket and towel if you need to open the P-trap under the sink.
Try boiling water first
Boil a full kettle or large pot of water. Remove any standing water from the sink if you can. Pour the boiling water directly into the drain in two or three stages, waiting a few seconds between pours. The heat melts soap scum and loosens grease that may be causing the blockage. This alone fixes a surprising number of slow drains. Wait a minute and see if the water drains normally.
Heads up: Do not pour boiling water into a porcelain bowl or a drain connected to PVC pipes that are already cracked or old. If you have PVC pipes and are unsure of their condition, use very hot tap water instead of boiling. PVC drain pipe is rated for a maximum operating temperature of 140°F, and boiling water is 212°F, so it softens the plastic and the solvent-welded joints rather than the clog.
Pull out visible debris
If the boiling water did not clear it, the clog is probably physical. Remove the drain cover or stopper. Most pop-up stoppers twist counter-clockwise and lift out. Shine a flashlight into the drain. You will usually see a clump of hair, soap buildup, or food stuck in the first inch or two. Use needle-nose pliers, a bent wire hanger, or even a zip-tie with small notches cut into it to pull the debris out. This is unpleasant but extremely effective, especially in bathroom sinks and showers.
Use baking soda and vinegar
Pour half a cup of baking soda into the drain. Follow it with half a cup of white vinegar. You will hear fizzing. That is worth being honest about, because it is not the reaction eating the clog. Baking soda is a base and vinegar is an acid, and mixing them neutralizes both into sodium acetate, water and carbon dioxide gas. What you get is fizz and salty water. The bubbling can lift light debris and loosen a film, which is useful, and the hot flush afterwards does most of the real work. Cover the drain with a wet cloth or plug to keep the pressure directed downward. Wait 15 to 30 minutes. Then flush with another pot of boiling water or very hot tap water. Between the fizzing and the hot flush, this shifts light soap scum and food residue without putting anything corrosive in your pipes. It will not dissolve a plug of grease, and nothing you pour from a kitchen cupboard will.
Good to know: For kitchen sinks with grease buildup, add a squirt of dish soap before the boiling water flush. Dish soap is a degreaser and helps break down the oily residue that baking soda alone might not dissolve.
Clean the P-trap if the clog persists
The P-trap is the curved section of pipe under the sink shaped like the letter P or U. Place a bucket underneath it. Unscrew the slip nuts on both ends by hand. Most P-traps have plastic nuts you can turn without tools. Pull the curved section down and let the water drain into the bucket. Check inside for clogs. You will often find a solid plug of gunk in the curve. Clean it out, rinse the trap, and screw it back on. Run water to check the seal for leaks.
Prevent future clogs
Use a mesh drain cover over shower and bathroom drains to catch hair before it goes down. In the kitchen, scrape plates into the trash before rinsing. Never pour cooking grease or oil down the drain. It solidifies inside the pipe and builds up over time. Once a month, run a kettle of hot water down the drain with a squirt of dish soap, which is the part that actually moves grease, and add the baking soda and vinegar first if you like the fizz. It takes about a minute and keeps buildup from reaching the point of a full clog.
Those four methods between them reach everything sitting in the first few inches of pipe, which is where household clogs live, and anything left after that is deeper than the sink. We keep a box of baking soda under the kitchen sink and run the monthly flush with hot water and dish soap, which takes about a minute and keeps things moving. If none of these worked and the water still will not drain, the clog might be deeper in the main line. That is the one situation where calling a plumber actually makes sense. But try the simple stuff first. If the problem is a clogged toilet rather than a sink or shower drain, that requires a different approach. Our guide on how to unclog a toilet covers plunging technique, the hot water trick, and when a toilet auger is the right call.
Questions we get asked about this
Answers from experience, not a textbook.
They work in some cases, but we do not recommend them as a first choice. Poison Control lists their working ingredients as enzymes, sulfuric and hydrochloric acids, and sodium and potassium hydroxide, which is to say strong acids and strong alkalis. They can corrode older pipes and damage garbage disposals, and they do not work well on solid clogs like hair balls. Two specific hazards are worth knowing. Poison Control warns that injury happens when the product splashes back, which is most likely if you pour from too high up or empty too much into a drain that is already completely blocked. And never follow one cleaner with another. Washington State's health department notes that bleach reacts with drain cleaners and other acids to give off chlorine gas, which irritates eyes and airways at low levels. If someone swallows any of it, gets it on their skin or breathes the fumes, call Poison Control on 1-800-222-1222. The mechanical and natural methods in this guide are safer for your pipes and just as effective for most household clogs.
Buildup inside the pipe can smell even when water drains fine. Bacteria feed on the gunk coating the pipe walls. A hot water flush with a squirt of dish soap usually clears the film they are feeding on, which is what clears the smell. If the smell is like rotten eggs, it could be a dried-out P-trap. Run water for 30 seconds to refill the trap and block sewer gas from rising up.
Yes, a flat-bottom cup plunger works on sinks. Fill the sink with a few inches of water first so the plunger cup can create a seal. Cover the overflow hole with a wet rag to maintain pressure. Pump the plunger up and down vigorously for 15 to 20 seconds. This can dislodge clogs that are just past the drain opening. It does not work well on deep clogs or grease buildup.
Call a plumber if multiple drains are clogged at the same time, which indicates a main sewer line issue. Also call if you have tried all the methods above and the drain is still blocked, if you notice water backing up into other fixtures when you flush or run the sink, or if there is a persistent sewer smell that refilling the P-trap does not fix. Main line clogs require a professional drain snake or camera inspection.
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