How to Clean a Smelly Sink Drain | Trav's Plumbing & HVAC LTD.
When your sink smells bad, it can make your whole kitchen or bathroom feel dirty—even if everything else is spotless.
The good news?
Most smelly drains are easy to fix at home with simple steps and a few household ingredients.
This guide walks you through the fastest way to clean a smelly sink drain, how to deep clean stubborn odours, and when it’s time to call a plumber.
Why Your Sink Drain Smells in the First Place
Before you start cleaning, it helps to know what you’re dealing with.
A smelly or stinky sink drain usually comes from one of these:
1. Food stuck in the drain
Common in kitchen sinks—especially when grease cools and hardens in Manitoba winters.
2. Bacteria buildup
Warm, wet pipes are a perfect place for bacteria that create that rotten-egg or sewer smell.
3. A dry P-trap
If a sink isn’t used often, the water barrier in the P-trap evaporates, letting sewer gases into the home.
4. Hard water mineral deposits
Southern Manitoba has mineral-heavy water.
Over time, it creates buildup that traps odours.
5. Septic system odours
If you’re rural, smells can back up into sink drains when the system is under strain.
If your sink smells like rotten eggs, sewage, mould, or chemicals, the steps below will help you identify the cause and get rid of it.
Quick Fix: The Fastest Way to Clean a Smelly Sink Drain
If you want the odour gone right now, start with this:
Step 1: Flush with hot, soapy water
Boil a kettle, add a big squeeze of dish soap, and slowly pour it down the drain.
This cuts through grease and removes the worst of the smell.
Step 2: Pour another flush of boiling water
If you have PVC pipes, let the water sit for a moment before pouring.
Boiling water directly on plastic pipes can cause issues if the plumbing is older.
If the smell improves—but doesn’t disappear—move on to the deep clean.
How to Clean a Stinky Sink Drain with Vinegar and Baking Soda
This is one of the easiest and most natural ways to clean a drain, and it works especially well for bacteria-related odours.
You’ll need:
½ cup baking soda
1 cup white vinegar
Hot water
What to do:
Pour the baking soda down the drain.
Slowly add the vinegar.
Let it foam for 10–15 minutes.
Rinse with hot water.
This method breaks down gunk, deodorizes the pipe, and helps loosen buildup.
It’s safe for most plumbing systems, including septic tanks.
Deep Clean: How to Get Rid of Smelly Drains When the Odour Keeps Coming Back
If the vinegar method didn’t fully solve it, here’s the plumber-approved deep clean.
1. Clean the stopper or strainer
These collect hair, food, soap scum, and bacteria.
Remove it and scrub with dish soap and a brush.
2. Clean the P-trap (if you’re comfortable doing so)
The P-trap is the curved pipe under your sink.
Place a bucket underneath, unscrew the connectors, empty it, and wash it out.
This usually solves persistent bathroom sink smells.
3. Use an enzymatic cleaner
Unlike chemical drain cleaners, enzyme cleaners eat organic buildup without damaging pipes.
These are great if your home is on a septic system.
4. Flush the venting system (indirectly)
If your drain gurgles and smells like sewage, the issue might be a blocked vent pipe.
Running hot water with the bathroom fan on won’t fix it, but it can help confirm the problem.
If you suspect a venting issue, a plumber needs to check it.
Why Does My Sink Drain Smell Like Sewer?
A sewer smell usually means one of these:
The P-trap is empty or cracked
The vent is blocked
The drain line has buildup producing sulphur gases
A septic tank issue is causing backflow of odour
If the odour smells like rotten eggs and spreads beyond the sink, skip to the “When to Call a Plumber” section.
My Sink Smells Worse After Cleaning — Why?
This can happen when:
Vinegar loosened buildup, but it didn’t fully flush out
Grease farther down the pipe hardened
The stopper wasn’t cleaned
Drain chemicals mixed with leftover cleaners (never mix bleach and vinegar)
A second flush with hot, soapy water usually clears it.
How to Prevent a Stinky Sink Drain
To keep odours from coming back:
Run hot water for 20-30 seconds after washing dishes
Never pour grease down the sink
Use a baking soda + hot water flush weekly
Clean the stopper every few weeks
Keep rarely used sinks from drying out by running water weekly
Hard water areas like Southern Manitoba benefit from the occasional vinegar flush to dissolve minerals.
How to Tell When the Problem Isn’t DIY Fixable
Call a plumber if you notice:
A constant sewer smell that returns within hours
Gurgling noises
Slow draining + odour together
Smells coming from multiple drains
Sudden odours after heavy rain (can indicate a septic or venting issue)
Rotten-egg smell from BOTH hot and cold water (a water heater issue)
These point to deeper plumbing problems a homeowner can’t fix from the sink.
Having Persistent Drain Smells? Trav’s Plumbing & HVAC Can Help.
If you’ve tried these steps and the smell keeps coming back, there’s likely something deeper going on—like a venting issue, a partially blocked drain line, or a dry or faulty P-trap.
Trav’s Plumbing & HVAC LTD helps homeowners across Southern Manitoba diagnose and eliminate stubborn drain odours.
Whether it’s a simple fix or a larger plumbing issue, we’re here to help get your home smelling fresh again.
FAQs
How do I get rid of the smell in my sink drain?
The fastest way is to flush the drain with hot, soapy water, then clean it with baking soda and vinegar. Pour ½ cup of baking soda into the drain, slowly add 1 cup of vinegar, let it fizz for about 10–15 minutes, and finish with hot water. If the smell keeps coming back, clean the stopper, check the P-trap, or use an enzymatic drain cleaner.
What is the best cleaner for smelly drains?
For most sink smells, a mix of baking soda and vinegar is the best natural option. For deeper odours caused by organic buildup, an enzymatic cleaner works better because it breaks down gunk without damaging pipes. If the smell is coming from sewer gas, the issue might be a dry or faulty P-trap rather than something you “clean” with a product.
What happens if you put too much baking soda in a drain?
Not much — baking soda won’t damage your plumbing. But using too much can clump up if it isn’t flushed properly, especially in older or narrow pipes. If that happens, run hot water or repeat the vinegar flush to dissolve any leftover powder.
Is bleach or vinegar better for drains?
Vinegar is usually the safer choice because it deodorizes and dissolves buildup without harming pipes or septic systems. Bleach can disinfect drains, but it should never be mixed with other cleaners — especially vinegar — because it creates toxic fumes. Bleach is also harsh on plumbing over time, so use it sparingly.
