A washing machine smells because of one of three things: a build-up of detergent residue, body oils and mould in the drum and door seal, dirty water sitting in the drain pump filter, or sewer gas coming back up the drain hose. The safe fixes are a hot empty wash with washing soda or a machine cleaner, a scrub of the door seal and detergent drawer, a clean of the pump filter and a check of the drain hose. A burning or electrical smell is different. Switch the machine off at the wall and call a licensed technician, because that is a motor, wiring or control board fault rather than a cleaning job.
We get asked why does my washing machine smell constantly, and the answer is nearly always the same. Modern machines run cool, use less water and are sealed tighter than the old top loaders, so anything that does not rinse away stays inside and grows. The good news is that a musty washing machine is almost always a cleaning problem, not a repair problem.
Why does my washing machine smell?
The smell is biofilm. Every wash leaves a thin film of detergent, softener, skin oils and lint on the drum, the outer tub you cannot see, the door seal and the hoses. In a warm, damp, closed machine that film grows mould and bacteria, and the result is the sour, musty smell that gets into clean clothes.
A few habits make it worse. Washing mostly on cold or 30°C never gets hot enough to break the film down. Using too much detergent, or fabric softener on every load, leaves more residue than the rinse can remove. And leaving wet washing in the drum for hours gives mould the perfect start.
Front loaders suffer most because the door seal has folds that hold water and lint, and the pump filter holds a little water between washes. Top loaders are not immune: the grey waxy scrud that forms under the agitator smells just as bad.
Mouldy, sewer or burning: which smell you have
A musty, damp or sour smell, strongest when you open the door, is mould and biofilm in the drum and seal. That is the classic washing machine smells mouldy complaint and it responds to cleaning. A rotten egg or drain smell is sewer gas coming back through the drain hose or the standpipe, and it is a plumbing and hose problem rather than a drum problem. A hot, burning or fishy electrical smell during a cycle is not a cleaning job at all. Turn the machine off at the power point straight away and do not run it again until a technician has looked at it.
How to get rid of smell in a washing machine: the deep clean
This is the routine we recommend when a washing machine smells and the cause is mould or residue. It is the real answer to how to get rid of smell in washing machine drums for good, and it works on front and top loaders. Do it with the machine empty.
- Run the hottest cycle the machine has, usually 90°C or a drum clean program, with a cup of washing soda or a commercial washing machine cleaner in the drum. Skip the detergent.
- Run a second hot cycle with two cups of white vinegar in the drum to shift what the first cycle loosened. Do not put the vinegar and the washing soda in the same cycle.
- While the drum is warm, wipe the door glass and the top of the drum opening, where residue sits out of reach of the water.
- Leave the door and drawer open overnight to dry the machine right through.
One deep clean will fix a mild smell. A machine that has been neglected for years may need the routine twice, and expect black flakes of loosened mould in the next couple of washes. Our full guide on how to clean a washing machine covers the top loader version of this as well.
The door seal, the drawer and the drain pump filter
A hot wash cleans the drum but misses three places where the smell actually lives. Pull back the lip of the door seal on a front loader and you will usually find black mould and a slurry of lint and hair in the fold. Scrub it with a paste of bicarb soda and water on an old toothbrush, wipe with vinegar, then dry it. Black staining that will not shift means the mould has grown into the rubber, and the seal will need replacing eventually.
Pull the detergent drawer right out, usually by pressing a tab at the back, and wash it in hot soapy water. Clean the cavity as well, especially the roof, where grey mould collects unseen.
Then the drain pump filter. On a front loader it is behind a small flap at the bottom front. Put a tray and towels down, drain it through the emergency hose if there is one, then unscrew the cap. Clear the coins, hair clips and lint, rinse the filter, and screw it firmly back in. A filter that has never been cleaned can be the whole cause. If the machine has also been slow to empty, read our guide on a washing machine not draining, because the two problems share a cause.
A sewer smell: check the drain hose and the standpipe
If the washing machine smells of drains rather than mould, look behind it. The drain hose should loop up to at least the height of the top of the drum before dropping into the standpipe or the laundry tub. A hose that runs downhill straight into the drain, or is pushed too far into the standpipe, lets sewer gas come back through the machine. There should also be a water trap in the standpipe. If the laundry has been unused for a while the trap may have dried out, and running water into it for a minute will refill it.
A hose that is kinked, partly blocked with lint or sitting in a puddle behind the machine also breeds smell. Pull the machine out, check the hose along its length, and look for any dampness underneath, which we cover in our guide to a washing machine leaking.
When a smelly washing machine needs a technician
Everything above is safe to do at home. Where it stops is anything electrical or inside the cabinet. A burning smell, a smell of hot plastic or rubber during the spin, or a machine that trips the power point needs a licensed technician, not a clean, because the fault is the motor, a belt, wiring or the control board. A drain pump that hums but will not empty, water that stays in the drum after the filter is clean, or a persistent sewer smell after the hose and standpipe are right also point to a pump or plumbing fault. A torn or deeply mouldy door seal is a straightforward replacement for a technician.
That is where our team comes in. CAI Appliance Services repairs washing machines across Perth, with fully qualified mobile technicians who come to you. We are an authorised service agent for Bosch and Electrolux, and we repair all major brands including LG, Samsung, Miele, Fisher and Paykel, Smeg and Whirlpool, so the work is done with the correct parts. Call CAI on 0415 343 413 to book a technician.
Washing Machine Smells? Why and How to Fix It: the quick version
Save or print this checklist before you book.
Frequently asked questions
Why does my washing machine smell like rotten eggs?
Why do my clothes smell musty after washing?
Can I use bleach to clean a smelly washing machine?
How often should I clean my washing machine to stop it smelling?
Keep the laundry running properly with our guides on how to clean a washing machine, a washing machine not draining and a washing machine leaking, or book a Perth technician with CAI.
