Safety first
Before your hand or a brush goes anywhere near the disposal opening, turn it off and cut the power — unplug it under the sink or switch off its breaker. Never put your fingers into a disposal that could turn on. With the power off, you can safely reach and scrub.
Why your disposal stinks
The smell is rotting food and the bacteria feeding on it, hiding in three places: the underside of the rubber splash guard (the flaps at the opening), the walls of the grind chamber, and the drain below. The splash guard is the biggest offender because running water never rinses its underside — gunk just accumulates there. That's why a disposal can smell even when you run water through it every day.
Step 1 — Scrub the splash guard
This single step fixes most disposal odour:
- With the power off, lift or fold back the rubber flaps.
- Using an old toothbrush or a small scrub brush and a little dish soap, scrub the underside and grooves of the splash guard thoroughly.
- You'll see grey, greasy gunk come off — that's the smell. Rinse and repeat until the rubber is clean.
Step 2 — Clean the grind chamber
- Pour in half a cup of baking soda, then one cup of white vinegar.
- Let it fizz for 5–10 minutes — the reaction loosens residue and deodorises.
- Flush with hot (not boiling) water while running the disposal for a few seconds. (Boiling water can soften and harm the plastic parts.)
Never add bleach to the vinegar — mixing bleach and vinegar releases toxic chlorine gas. Baking soda and vinegar are all you need here.
Step 3 — Scour with ice, freshen with citrus
- Drop in a couple of handfuls of ice cubes (freezing white vinegar into cubes works even better) and run the disposal with cold water. The ice scours built-up grime off the grinding components.
- Follow with citrus peels — lemon, lime or orange — ground with cold water. They leave a fresh scent and help cut grease.
Ice doesn't sharpen anything (disposals use blunt impellers, not blades), but the abrasion genuinely cleans the chamber.
How to keep it from smelling again
- Run cold water for several seconds during and after every use so nothing is left sitting inside.
- Keep the wrong things out: grease and oil, coffee grounds, fibrous vegetables (celery, corn husks), pasta and rice, and bones. These clog, coat or ferment.
- Freshen weekly with citrus peels or ice.
- Scrub the splash guard every week or two before the gunk builds up.
Most disposal odour is entirely preventable — don't let food sit in it and the smell never gets a foothold.
If the smell isn't the disposal
If you've cleaned the disposal top to bottom and the sour smell persists, the source may be further down — a drain lined with biofilm, a dry or blocked P-trap, or (if you're also seeing small flies) drain flies breeding in the pipe. Our guide on getting rid of fruit flies and drain flies covers the drain-cleaning side. A smell that returns fast despite a clean disposal, or a slow drain that comes with it, can point to a plumbing issue worth a professional look.
When the kitchen needs more than a disposal clean
In a commercial kitchen, sink and drain odours usually trace back to grease build-up in traps and lines — a job for a proper back-of-house deep clean, not a cup of vinegar. Our commercial kitchen cleaning and restaurant cleaning services tackle the grease and drain build-up that make kitchens smell across the GTA. Get a free quote if odours keep coming back.
Frequently asked questions
Why does my garbage disposal smell so bad?
Trapped, rotting food — mostly on the underside of the rubber splash guard, plus the chamber walls and drain. The splash guard never gets rinsed by running water, so gunk sits and smells there.
How do you clean a smelly garbage disposal?
Power off, scrub the splash guard's underside with a toothbrush and dish soap, then pour in half a cup of baking soda and a cup of vinegar, let it fizz, and flush with hot water while running it. Finish with ice and citrus peels.
Do ice cubes really clean a garbage disposal?
Yes — grinding ice scours grime off the grinding components (vinegar ice cubes work even better). It doesn't sharpen blades; disposals use blunt impellers. Add citrus peels after for scent and to cut grease.
Can you put bleach in a garbage disposal?
Not routinely — it can harden grease into a clog and damage parts, and must never be mixed with vinegar. Baking soda, vinegar, dish soap, ice and citrus clean it safely instead.
How do I keep my garbage disposal from smelling?
Run cold water a few seconds after every use, keep out grease, coffee grounds, fibrous veg and starches, grind citrus or ice weekly, and scrub the splash guard regularly. Most odour is preventable.