To get rid of a smelly sink drain, pour 12 12 cup of baking soda down the drain followed by 1 cup of white vinegar. Let the mixture fizz for 10-15 minutes, then flush it completely with a full kettle of boiling water.
How to stop the smell
Pouring salt down your drain at night is a popular DIY plumbing trick used for routine maintenance. The goal is to take advantage of the salt's coarse texture and natural moisture-absorbing properties.
You can also deodorize drains and help smelly drains with a combination of baking soda and vinegar. These ingredients, when used together, can also sometimes help to clear drain clogs.
When a kitchen sink smells but drains properly, the issue is almost always biofilm (a layer of trapped food particles, grease, and bacteria) inside your drainpipes, a dry P-trap letting up sewer gases, or a foul odor trapped inside a garbage disposal.
Here are some top-rated options:
While the rotten egg smell is the most alarming of all drain odours, the vast majority of cases are resolved by simply refilling the P-trap seal or performing a thorough deep cleaning to eliminate H2S-producing bacteria.
Baking soda and vinegar do not effectively unclog drains. Instead of clearing debris, mixing them chemically neutralizes both ingredients into salt water. The fizzing reaction is visually satisfying but largely escapes upwards, offering zero power to dissolve grease, hair, or stubborn sludge.
Sink drains most commonly smell like sewage due to a dry P-trap, a buildup of slimy bacteria (biofilm) in the pipes, or blocked plumbing roof vents.
The characteristic "old age smell" is scientifically known as nonenal (or 2-nonenal). It is a chemical compound produced when the skin's natural oils and fatty acids break down and oxidize as we age.
We highly recommend this practice, and often people ask “why pour salt down the drain?” The answer is that salt will break down grease and emulsified fats by itself, and especially when combined with vinegar and hot water it can contribute to clearer pipes.
Plumbers highly recommend avoiding harsh chemical drain cleaners, as they can corrode pipes and only offer temporary relief. Instead, they suggest preventing buildup through daily habits, using natural enzyme or enzymatic cleaners for maintenance, and letting professional cleaners clear severe blockages.
Salt itself will not chemically damage PVC pipe; the material is chemically inert and highly resistant to saltwater and brine. However, salt can indirectly cause issues for your plumbing system. While the plastic remains unaffected, salt can corrode connected metal fittings, dry out joints, or potentially damage downstream fixtures like water heaters.
Vinegar and baking soda
For this method, pour ½ cup baking soda into the drain opening, then follow this with 1 cup of vinegar. The ingredients will start to react, so plug the drain with a stopper or old rag to seal in the solution. Wait for 30 minutes – 1 hour, then flush the mixture from the drain with hot water.
Items to Never Flush or Pour Down the Drain:
Bacterial growth: Inside your drain, there are bacteria that feed on organic matter. Static water can build up in the P-trap, the U-shaped pipe beneath the drain, when the bathroom fixture doesn't run for a while. This stagnant water turns into a haven for germs, which give out foul smells.
Baking soda and vinegar
Pour half a cup of baking soda into the drain, followed by a half cup of white vinegar. Plug the drain with the stopper and let the mixture work for 15 to 30 minutes.
[4,5] In the case of low levels of exposure (0.05 ppm), early signs and symptoms include the smell of rotten eggs, fatigue, headaches, nausea or vomiting, dizziness or lightheadedness, and poor memory and concentration.
Drano can work well if your drain smells bad due to minor clogs. If food, grease, or soap buildup is causing slow drainage and mild odors, it may clear things up. However, if the issue is sewer-related or due to bacteria, it won't be much help.
A straightforward yet effective approach to addressing a clogged drain pipe involves simply using hot water mixed with dish soap. This method, ideal for tackling minor blockages, leverages the degreasing power of dish soap combined with the force of hot water to dislodge and dissolve clog-causing residue.
Pouring boiling water down your drain can soften and warp PVC pipes, weaken the glue in pipe joints, and damage rubber gaskets. Instead of clearing grease, boiling water just melts it, pushing it further down the pipe where it hardens and creates a stubborn, hidden clog.
For minor clogs or routine maintenance, the baking soda and vinegar method typically takes 15 to 30 minutes to sit in the drain. For tougher, stubborn blockages, leaving the mixture to work for several hours or overnight is recommended.
A sewer smell coming from your sink usually means sewer gases are escaping into your home. The cause is typically a dry P-trap, a blocked plumbing vent, or a buildup of bacteria-rich sludge in your pipes.
It is not recommended to pour bleach down your sink to eliminate odors. While it temporarily kills surface bacteria, bleach is corrosive to pipes, can ruin the rubber seals in your plumbing, and will not dissolve the underlying grime—like hair and soap scum—that causes the smell.
Getting rid of a rotten egg smell requires isolating the source, which is usually hydrogen sulfide gas from bacteria, spoiled food, or a plumbing issue.