Why Does Washing Machine Smell and How to Fix It

Why Does My Washing Machine Smell?

A smelly washing machine is one of the most common appliance complaints — and it's almost always caused by one or more of these factors: mold and mildew growth, detergent and fabric softener buildup, a clogged filter, or a blocked drain hose. Identifying the specific cause helps you fix it faster and prevent it from coming back.

Cause 1: Mold and Mildew (Most Common)

Smell: Musty, earthy, like a damp basement

Mold thrives in the warm, moist environment inside a washing machine — especially in the rubber door gasket of front loaders, the drum, and the detergent drawer. If you close the door immediately after a cycle, moisture gets trapped and mold grows rapidly.

Fix:

• Run a hot cleaning cycle with Affresh Washing Machine Cleaner
• Clean the rubber seal with OLELON Mold Stain Remover Gel
• Clean the detergent drawer and filter
• Always leave the door open after every cycle going forward

Cause 2: Detergent and Fabric Softener Buildup

Smell: Sour, stale, or chemical odor

Using too much detergent, the wrong type of detergent (non-HE in an HE machine), or fabric softener creates a thick residue inside the drum, hoses, and pump. This residue becomes a food source for bacteria and develops a sour smell over time.

Fix:

• Run 2–3 consecutive hot cycles with white vinegar (2 cups per cycle) to dissolve buildup
• Switch to HE detergent and use the correct amount
• Consider switching to laundry pods placed directly in the drum to eliminate drawer buildup

Cause 3: Clogged Filter

Smell: Sewage-like, rotten, or very strong musty odor

A filter clogged with lint, hair, and debris develops a strong, unpleasant odor as trapped organic matter decomposes. This is especially common if the filter hasn't been cleaned in months.

Fix:

• Locate and clean the pump filter (see our guide on cleaning the washing machine filter)
• Clean monthly going forward

Cause 4: Blocked or Kinked Drain Hose

Smell: Sewage or sewer gas smell

If the drain hose is kinked, partially blocked, or incorrectly installed, water can pool inside and develop a sewage-like odor. Check that the hose is not kinked and is properly inserted into the standpipe.

Fix:

• Inspect the drain hose for kinks or blockages
• If the hose is too short and causing improper drainage, replace it with a longer one like the HLMOptimo 10ft Drain Hose Extension

Cause 5: Leaving Wet Laundry in the Drum

Smell: Sour, mildewy

Leaving wet clothes in the drum for more than 1–2 hours allows bacteria to multiply rapidly, creating a sour smell that transfers to the laundry and the machine interior.

Fix: Remove laundry immediately after the cycle ends. If you forgot, rewash with a cup of white vinegar added to the cycle.

The Complete Smell Elimination Routine

1. Clean the rubber seal with OLELON Mold Remover Gel
2. Clean the detergent drawer
3. Clean the filter
4. Run a hot drum cleaning cycle with Affresh
5. Run a second hot cycle with 2 cups of white vinegar
6. Leave the door open to dry completely

Recommended Products

• Affresh Washing Machine Cleaner — eliminates odor-causing buildup throughout the machine
• OLELON Mold Stain Remover Gel — removes mold from the rubber seal and drawer
• Iberia White Vinegar — dissolves detergent buildup and kills odor-causing bacteria
• HLMOptimo Drain Hose Extension — fix drainage issues that cause sewage odors