Why Your Washing Machine Drain Smells + How to Fix It

When a washing machine drain starts smelling, be quick to question the last time your drain hose, drain pump, or drain pump filter were cleaned.

These areas collect detergent residue, fabric softener buildup, lint, and even odor-causing bacteria.

Cleaning them helps remove sewer smell and stops water backup before it turns into a bigger problem. This process is simple, and you may only need basic items like baking soda, white vinegar, or a small plumber's snake if the drain line is clogged.

We do this every few years, but it surely has to do with your laundry routine, the detergents you use, and your home's plumbing system. You may want to do it annually... and you might never find a need to do it at all.

Why Washer Drains Smell

The inside of a washer stays damp, which makes it easy for grime to collect in tight spaces.

A few things tend to trigger those washing machine drain smells:

Detergent residue stuck in the drain hose or drain lines
A clogged drain pump or drain pump filter blocked by lint
A dirty drain trap holding stagnant water
A vent pipe connected to house drains that’s not moving sewer gases out
A rubber seal or door seal holding mildew

Sometimes the smell resembles sewage smells or hydrogen sulfide gas from sewer gasses or septic gasses coming back through the laundry drain. When this happens, a damaged sewer gas seal or vent pipes not pulling air the right way may be involved; however, most of the time the odor is still coming from buildup inside the washer’s own drain system.

Drainage hose loops around behind a washing machine. — The drainage hose loops around behind the machine; there's always some water sitting in there. Credit: Emily Fazio

How to Clean Your Washing Machine Drain

Start simple. You don’t need special cleaning hacks or chemicals, and you don’t need to take the machine apart. Work through the parts in the order below.

1. Clear the drain pump filter.

Front-load machines almost always have a small drain plug and filter near the bottom. Pulling it out helps release trapped debris and can stop a sewer odor fast.

Put a tray underneath to catch water.

Do a visual check, too. Look for:

Hair and lint stuck in the filter
Coins or buttons
Thick detergent paste

Rinse the filter and slide it back in place.

2. Flush the drain hose

A clogged drainage problem often starts here:

Detach the drain hose from the back of the washer and the drain tube attached to the wall. Yes, it's a pain to access the back of the washer, but if you slide it straight out, it makes the job a lot easier.
In the sink, run warm water through the drain.
Water should pass through, but sometimes a gentle pass with a plumber's snake can remove extra sediment in the hose.

3. Clean the drain line or laundry drain

If the laundry drain in your sink slows down or smells, pour a mix of baking soda and distilled white vinegar down it.
Let it fizz for about 15 minutes. This simple odor removal step also helps with sewer gas coming back through the pipe.

4. Freshen the drum and internal seals

Even if the main smell is from the drain, the rubber door gasket and internal seals can hold extra grime.

Wipe them with a mix of white vinegar and a few drops of tea tree oil.
Run a rinse cleaning cycle afterward to rinse it away before doing laundry.

Washing machine from GE with labels in Spanish.

Why Washing Clothes in Cold Water Just Makes Sense

Cold water temperatures save energy, protect clothes, and lower bills with no extra effort.

Maintenance Habits That Help Prevent Smells

Once the drain parts are clean, a few simple habits keep them that way:

Avoid too much detergent or fabric softener
Wipe down the detergent compartment more often
Leave the door open between loads (seriously, it needs to air out!)
Clean the lint trap on older top-load machines
Pull out the drain pump filter every month
Make sure the plumbing vent near the laundry room is not blocked

Some people worry about water leak issues during cleaning, but as long as you secure the drain hose and check pump systems afterward, leaks are rare.

Man empties the washing machine in a modern home. — A clean machine = clean laundry. Credit: simon2579 / Getty Images

FAQ

Why does my washer smell even after cleaning the drum?

The drum isn’t usually the source. Smells almost always hide in the drain pump filter, drain hose, or drain trap. If sewage smells linger, the plumbing pipes or vent pipe connected to house drains may need attention from a pro.

Understanding Basement Floor Drains: What Every Homeowner Should Know

Learn more about the different types of drains that keep your basement dry and protect your home from water damage.

Is sewer gas dangerous coming from a laundry drain?

Small amounts of sewer gas or sewer gases drifting from a washer drain can come from a dried-out trap. Refreshing the trap with water usually fixes it. If the smell resembles hydrogen sulfide gas and stays strong, a plumber can check the sewer gas seal.