Quick Answer:
If you notice a heavy greasy smell at the sink after cooking, start by wiping the sink rim and the disposal splash guard. Then run hot water with a small amount of dish soap for about a minute, scrub the underside of the rubber baffle, and finish by rinsing with hot water to flush loosened grease away. If the smell continues or you have slow draining, read the rest of the steps and consider professional help.
Why This Happens
Grease and oily food particles collect on the sink rim, the rubber splash guard (baffle), and inside the disposal chamber. As grease cools it clings to surfaces and traps food scraps. Bacteria feeding on trapped grease produce a strong, greasy or sour odor. Sometimes the smell is mixed with other scents from trapped food — think of issues like Rotten food smell under sink when material is left to sit in dark, damp places.
Step-by-Step What to Do
Tools and prep
- Soft cloth or paper towels
- Small scrub brush or an old toothbrush
- Dish soap and a heat-safe source of hot water (tap water is fine)
- Tongs or pliers (do not put your hand in the disposal)
1. Wipe the sink rim and splash guard
Lift the rubber splash guard (baffle) and wipe the rim of the sink where it meets the disposal. Wipe the top and underside of the splash guard as you can reach it. A greasy ring often forms at the edge and is a common source of odor.
2. Run hot water and dish soap
Turn the cold tap to a steady hot stream and add a small squirt of dish soap into the running water. Let hot, soapy water run into the disposal for about one minute to help soften and loosen grease. Keep the disposal switched off while doing this unless you need to run it briefly to flush—only run it with water flowing.
3. Scrub the underside of the rubber baffle
Use a small brush or toothbrush to scrub the underside of the rubber baffle and the immediate opening of the disposal. Work carefully with tongs if you need to angle the baffle to reach stubborn grease. Scrubbing dislodges the greasy film so the rinse can carry it away.
4. Rinse with hot water to clear loosened grease
After scrubbing, run hot water for another minute to flush the loosened grease out of the opening. If you run the disposal briefly during this rinse, keep the water flow steady. Wipe any remaining residue on the sink rim.
What Not to Do
- Don’t dump melted grease or oily pan scrapings into the disposal to “wash it down”—it re-coats the chamber and trap and makes odors worse over time.
- Don’t assume a persistent greasy smell with slow draining is fixed by surface cleaning; if the odor comes with slow draining, professional cleaning may be needed to clear the trap and drain line.
When to Call a Professional
Call a plumber if:
- The odor persists after you follow the cleaning steps.
- The smell returns quickly after cleaning or you notice raw sewage or gas-like smells—this can indicate a deeper trap or vent problem or a failing seal. In those cases Odor returns after cleaning is a sign to get expert help.
- You have slow draining, gurgling, or repeated clogs that don’t respond to normal clearing methods.
Safety Notes
- Always turn the disposal off at the switch before working near it. If possible, disconnect power at the breaker for extra safety.
- Never put your hand inside the disposal. Use tongs or long-handled tools to remove objects.
- Avoid strong chemical drain cleaners—these can damage the disposal and pipes and are hazardous to handle.
- Work in a well-ventilated area if odors are strong. If you smell gas or sewer gas, leave the house and call a professional immediately.
Common Homeowner Questions
- Q: How often should I clean the splash guard? A: Wipe it monthly or whenever you notice grease build-up.
- Q: Will running hot water and soap harm the disposal? A: No. Hot water and a small amount of dish soap are safe and help loosen grease.
- Q: Can I use citrus peels to freshen the disposal? A: Occasional citrus can help with light odors, but it won’t remove a grease coating—follow the cleaning steps above for that.
For more related articles, see the Food Waste Odors & Bio-Buildup hub.