How to Clean a Washing Machine: 5 Steps (Front and Top Load)

A washing machine that smells is not dirty in the usual sense. It has biofilm — a layer of bacteria and mould living on the residue of detergent, fabric softener and skin cells. It builds up fastest in cool washes, in hard water, and on the rubber door seal of a front loader.

Cleaning it properly takes about an hour of machine time and ten minutes of your attention. Here is the full routine for both front and top loaders.

Why washing machines smell

• Cool washes. Modern detergents work at 30°C, but so does bacteria. Without a hot cycle, biofilm accumulates.
• Excess detergent. Too much soap does not rinse out; it leaves a residue that feeds the biofilm.
• Fabric softener. The worst offender in a washer — it leaves a waxy film in the drum, the seal and the pipes.
• The door seal. Front loaders have a rubber gasket that traps water. It is warm, dark and wet — ideal for mould.
• A closed door. Sealing a wet drum between washes keeps the moisture in and the mould growing.
• Hard water. Scale gives biofilm something to grip, and it builds faster.

1. Run a hot empty cycle

1. Empty the drum completely. No laundry, no forgotten items.
2. Choose the hottest cycle the machine allows — 90°C if available, 60°C minimum.
3. Add the cleaner: a proprietary washing machine cleaner tablet, or 2 cups of white vinegar in the drum.
4. For heavy odour, add half a cup of baking soda directly to the drum with the vinegar for a stronger clean.
5. Let it run the full cycle, including the rinse and spin. This flushes loosened biofilm out of the drum and the pipes.
6. For a badly affected machine, run this cycle twice.

2. The door seal — the dirtiest part

On a front loader, peel back the rubber gasket around the door opening. You will almost certainly find dark slime, hair, lint and a puddle of standing water.

1. Pull the rubber lip back all the way around the drum opening.
2. Check the drain holes in the bottom of the gasket — these clog with lint and cause water to sit permanently.
3. Wipe the whole seal with a cloth soaked in dilute vinegar or an all-purpose cleaner.
4. Use a toothbrush for the folds and the corners where the mould actually lives.
5. For black mould, use a mould-specific cleaner and let it dwell. Do not scrub the rubber hard — you will tear it.
6. Dry it afterwards and check that the drain holes are clear.

3. The detergent drawer

The drawer and its housing accumulate a thick residue of undissolved detergent and softener. It is also where the water jets are, and they clog.

1. Remove the drawer — usually by pressing a release tab or pulling it out past a stop.
2. Soak it in hot water for 20 minutes, then scrub with an old toothbrush.
3. Clean the housing behind it with a bottle brush; this is where the black slime hides.
4. Clear the water jets with a pin if they are blocked.
5. Refit and run a rinse cycle to confirm the water flows through properly.

4. The drain pump filter

Most front loaders have a small access panel at the bottom front hiding the drain pump filter. It traps coins, hair, buttons and grit, and when it clogs the machine stops draining properly.

1. Put towels down — there will be water. Use a shallow tray.
2. Open the access panel and unscrew the filter cap slowly, letting the water drain.
3. Remove debris from the filter — coins, hair, lint and grit are typical.
4. Check the pump impeller behind the filter turns freely.
5. Refit and tighten — a loose filter cap leaks on the next wash.
6. Clean it every three months, and immediately if the machine stops draining.

5. Habits that prevent it coming back

• Leave the door ajar after every wash — the single most effective habit.
• Leave the detergent drawer slightly open too, so it dries.
• Use less detergent. Most people use double what they need. Excess soap is biofilm food.
• Skip fabric softener. It leaves waxy residue in the drum and the seal. Use wool dryer balls instead.
• Run one hot cycle a month even if you wash everything cool.
• Wipe the seal dry after the last wash of the day.
• Wash at 60°C occasionally for towels and bedding — it sanitises the machine as well as the laundry.

Front vs top loader differences

Frequently asked questions

A cleaning schedule to keep it fresh

Washing machines fail in two ways that are almost entirely preventable: smells from biofilm, and drainage faults from a clogged pump filter. Both are addressed by a routine that takes less than half an hour a month in total, and both are expensive to ignore — a machine that smells will keep smelling, and a blocked pump eventually floods the room.