Getting the Smell Out of a Washing Machine

The smell is biofilm, and it is being fed. Cold washes never get hot enough to kill it or to dissolve the fats holding it together, and over-dosed detergent leaves a residue for it to grow on.

So it comes in two parts: remove what is there, then stop feeding it. Do only the first and the smell is back within a couple of months, which is why people conclude machine cleaners do not work.

A note on this guide: this rests on how biofilm forms in the wet, cool parts of a washing machine and on manufacturers' stated maintenance-wash guidance, not on machines tested here. See how we test.

The problem, as it appears

Clean laundry that smells faintly of a damp cloth, sometimes only once it is dry, sometimes only on towels. A dark rim inside the rubber door seal. A detergent drawer with something growing under the lid.

Everything looks clean and everything smells wrong.

Why the obvious fix disappoints

The obvious fix is a machine cleaner, run once. It disappoints because it addresses the deposit and not the conditions.

Biofilm grows where three things coincide: moisture that never dries, a temperature that never gets high, and a food source. A modern machine used the modern way supplies all three — the door is closed after every wash, the washes are at thirty degrees or lower, and detergent is dosed by the cap rather than by the load.

Run a cleaner and the machine improves. Change nothing else and it regrows in exactly the same places, because those places are still wet, still cool and still being fed.

This page contains affiliate links. If you buy through them, Ugly Fixes may earn a commission at no extra cost to you. Products are selected independently.

What actually matters

1. A genuinely hot maintenance wash

The highest temperature the machine offers, empty, with a cleaner. This is the step that reaches the outer drum and the sump — parts you cannot see or wipe, and where a significant share of the smell lives.

2. The parts you can reach, by hand

The cleaner does not do these:

• The door seal. Fold the rubber back and wipe inside the lip. This is where the visible black growth is.
• The detergent drawer. It comes out on almost every machine. Wash it in hot water and clean the cavity it sits in, which is usually worse than the drawer.
• The filter, behind a hatch at the bottom of most front-loaders. Put a tray and a towel down first — there is more water behind it than the hatch suggests.

3. The habits that stop it returning

Two changes, both free:

• Leave the door and the drawer open between washes so everything dries.
• Dose detergent for the load and your water hardness, not to the top of the cap. Excess detergent is the food source.

A hot wash every month or two maintains the result.

The options, and who each suits

A machine cleaner, hot and empty

The first pass, and the one that reaches where you cannot.

Citric acid, if you are in a hard water area

Scale on the heating element is a separate problem that makes the machine less able to reach temperature — which makes the biofilm problem worse. In hard water areas the two run together.

An enzyme cleaner, for what came out smelling

For towels and sportswear that hold odour after the machine is clean. Enzymes break down the residues that ordinary detergent leaves behind, and they need a long soak rather than a spray and a wipe.

A cloth for the seal and drawer

Unglamorous and necessary. Nothing you pour into the drum reaches the underside of the door seal.

The mistake to avoid

Running a cleaner and changing nothing else. The smell goes, everyone is satisfied, and it returns in six weeks — at which point the conclusion drawn is that the product was ineffective, when the machine simply went back to the conditions that grew it.

The second mistake is more detergent, which is the instinctive response to laundry that smells and is the opposite of the fix. Excess detergent is the food source, and dosing up feeds the thing making the smell.

If clothes are also being dried indoors, that is a second source of damp working against you — laundry with nowhere to dry it covers where that water actually goes.