Why washing machines get smelly
A washing machine is warm, damp and fed a steady diet of detergent and fabric softener — ideal conditions for mould, mildew and bacteria. Residue collects in the spots water doesn't fully rinse: the rubber door gasket on front-loaders, the detergent drawer, and under the agitator on top-loaders. Leaving the door shut after a wash traps the moisture and lets it all grow. The result is the familiar musty smell that then transfers onto "clean" clothes.
The fix is two-part: run a hot cleaning cycle to clean the drum and hoses, and hand-clean the gasket, dispenser and filter where buildup actually lives.
Step-by-step: the monthly cleaning cycle
Empty the drum
Make sure the machine is completely empty — cleaning runs on an empty load, not with laundry in it.
Add your cleaner
Use one of: two cups of white vinegar, a half-cup of bleach, or a dedicated washing machine cleaning tablet. Vinegar goes in the drum (or dispenser); bleach goes in the bleach dispenser. Never combine bleach and vinegar — together they release toxic chlorine gas.
Run the hottest, largest cycle
Select the "clean washer" or "tub clean" cycle if your machine has one; otherwise use the hottest water setting and the largest load size. Let it run completely.
Wipe the drum and run a rinse
Wipe the inside of the drum with a clean cloth. If you used vinegar and want extra freshness, run a second short hot rinse with a half-cup of baking soda to clear any remaining residue.
Clean the parts the cycle misses
Hand-clean these every month
Leave the door (and the detergent drawer) open between washes so the inside can dry out. Mould and mildew need standing moisture — take that away and most washing machines never develop the musty smell in the first place. Using less detergent helps too; excess suds leave residue that feeds odour.
Front-load vs top-load: what's different
The cleaning cycle is the same, but the trouble spots differ. Front-loaders seal tightly and trap water in the door gasket, so the gasket and the drain filter are the key areas. Top-loaders don't have a gasket, but residue collects under the agitator, around the rim and in the fabric-softener cup — wipe those, and if you have a high-efficiency top-loader, still run the monthly hot cycle.
Frequently asked questions
How often should you clean a washing machine?
Run a cleaning cycle once a month, wipe the gasket and leave the door open after each wash, and clean the dispenser every few weeks. Regular maintenance is what prevents the musty smell rather than fixing it after the fact.
Should you clean a washing machine with vinegar or bleach?
Either works — vinegar dissolves residue and mineral buildup, bleach disinfects and tackles mould — but never use them in the same cycle, because the combination produces toxic chlorine gas. A dedicated washing machine cleaner is a good third option. Always run it hot, on an empty drum.
Why does my washing machine smell?
Mould, mildew and bacteria growing on trapped moisture and detergent residue, usually in the door gasket and dispenser. Leaving the door closed and overusing detergent make it worse. Clean those areas, run a hot cleaning cycle, and air the machine out between washes.
How do you clean a front-load washer gasket?
Peel back the rubber seal and wipe inside the folds with mild detergent or diluted bleach, removing hair, lint and buildup, then dry it. Leave the door open afterward. The gasket is the single biggest source of front-load washer odour.
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