Why Does My Washing Machine Smell Like Sewage Easy Cleaning Cycles To Fix It

If you've opened your washing machine only to be greeted by a stench resembling a sewer, you're not alone. This unpleasant odor is more common than many realize—and while alarming, it’s usually fixable without professional help. Sewage-like smells from your washer typically point to trapped moisture, bacterial buildup, or plumbing issues. Left unaddressed, the odor can transfer to your clothes and worsen over time. The good news: with targeted cleaning cycles and a few simple maintenance steps, you can restore freshness and prevent future problems.

What Causes a Sewage-Like Smell in Your Washing Machine?

The most frequent cause of a sewage odor isn't actually sewage—it's stagnant water mixing with organic matter like soap scum, fabric softener residue, hair, and lint. These materials accumulate in hidden areas of the washing machine, creating a breeding ground for anaerobic bacteria. As these microbes break down debris, they release hydrogen sulfide gas—the same compound responsible for rotten egg or sewer smells.

Common culprits include:

• Clogged drain pump filter: Debris blocks water flow, causing standing water that breeds odor.
• Mold in rubber door gaskets (front-loaders): Moisture gets trapped under the seal, promoting mold growth.
• Dirty detergent drawer: Residue builds up and decomposes over time.
• Infrequent use: Machines left idle allow moisture to stagnate.
• Plumbing backflow: In rare cases, sewer gases may enter via improper venting or a dry P-trap.

“Over 70% of washing machine odors stem from poor maintenance rather than major mechanical failure.” — Dr. Alan Reyes, Appliance Hygiene Researcher, National Home Efficiency Institute

Easy Cleaning Cycles to Eliminate the Smell

Your washing machine likely has built-in cleaning capabilities. Using them regularly prevents odor buildup and maintains performance. Below are three effective cleaning cycles—each designed for different needs and machine types.

1. Hot Water Sanitize Cycle with Vinegar

Ideal for both front- and top-loading machines, this cycle dissolves soap residue and kills odor-causing bacteria.

1. Remove any clothing or items from the drum.
2. Add two cups of white vinegar directly into the drum (not the detergent tray).
3. Select the hottest wash setting (e.g., “Sanitize” or “Clean Washer”) with the longest cycle duration.
4. Run the machine empty.
5. Wipe down the drum and gasket with a microfiber cloth afterward.

Tip: For extra disinfection, add ½ cup of baking soda along with the vinegar—but never mix vinegar with bleach.

2. Bleach Flush for Deep Disinfection

Use this method monthly if you live in a humid climate or notice persistent mildew.

1. Ensure no clothes are in the washer.
2. Pour 1 cup of chlorine bleach into the detergent dispenser.
3. Run a full hot water cycle on the heaviest soil setting.
4. Pause the cycle after it fills, then let it soak for 30 minutes before resuming.
5. After completion, wipe all accessible surfaces, including the door seal and dispensers.

This process destroys mold spores and neutralizes deep-seated bacteria. However, avoid using bleach on stainless steel drums too frequently, as it may cause corrosion over time.

3. Monthly Drum Clean Cycle (Built-In Feature)

Many modern machines have a dedicated “Clean Drum” or “Tub Clean” function. These cycles use high-pressure water and extended agitation to flush out debris.

To maximize effectiveness:

• Check your user manual for recommended frequency.
• Use manufacturer-approved cleaner or a natural alternative like citric acid.
• Follow each clean cycle with a quick wipe of the door gasket and dispensers.

Step-by-Step Maintenance Routine to Prevent Future Odors

Prevention is simpler and more effective than repeated deep cleans. Follow this weekly-to-monthly maintenance plan to keep your machine smelling fresh.

1. Leave the Door Open After Use: Especially for front-loaders, prop the door ajar for several hours post-wash to allow airflow and drying.
2. Clean the Door Gasket Weekly: Wipe the rubber seal with a vinegar-soaked cloth, checking folds for trapped lint or coins.
3. Remove and Clean the Detergent Drawer: Slide it out monthly and rinse under warm water to dissolve buildup.
4. Inspect the Drain Pump Filter: Located near the bottom front panel, this filter catches debris. Clean every 2–3 months.
5. Use High-Efficiency (HE) Detergent: Regular detergents leave excess suds that trap moisture and accelerate grime accumulation.
6. Avoid Overloading: Crowded loads reduce rinsing efficiency, leaving residue behind.

Mini Case Study: Sarah’s Front-Loader Turnaround

Sarah, a mother of two in Portland, Oregon, noticed her LG front-load washer emitting a strong sewer-like smell every time she started a load. She avoided using it for weeks, resorting to hand-washing essentials. After researching, she discovered her habit of closing the door tightly after each use was trapping moisture. Following a vinegar clean cycle and adopting the practice of leaving the door slightly open, the odor disappeared within a week. She now runs a maintenance cycle every four weeks and reports her machine runs quieter and smells neutral.

Do’s and Don’ts: Common Mistakes That Worsen the Problem

Do’s	Don’ts
Use vinegar or citric acid monthly for natural cleaning	Never mix bleach and vinegar—they create toxic chlorine gas
Run an empty hot cycle after heavy soil loads	Don’t use fabric softener excessively—it coats the drum and traps odor
Clean the door seal weekly in humid environments	Don’t ignore error codes related to drainage or spinning
Check hoses annually for cracks or kinks	Don’t overload the machine—it reduces cleaning efficiency
Store detergent in a dry place to prevent clumping	Don’t assume the smell will go away on its own

When the Smell Isn’t From the Machine: Plumbing Issues

Sometimes, the odor originates outside the appliance. If cleaning cycles don’t resolve the issue, consider these external factors:

• Dry P-trap: The U-shaped pipe under your standpipe or laundry sink can dry out, allowing sewer gases to escape. Pour a quart of water down the drain monthly to maintain the seal.
• Vent Pipe Blockage: Roof vents that allow sewer gases to escape can become clogged with leaves or nests. A gurgling sound during draining may indicate this issue.
• Cross-Connection: In older homes, improper plumbing may connect the washer drain to a sewer line without proper air gaps.

To test whether the problem is plumbing-related:

1. Smell near the laundry drain when the machine isn’t running.
2. If the odor persists even with the washer off, the source is likely the drain system.
3. Pour ¼ cup of vegetable oil down the drain—it floats and temporarily seals surface evaporation.
4. If the smell stops, a dry trap is confirmed.

Tip: Install a self-sealing drain cover to prevent evaporation in infrequently used laundry areas.

Frequently Asked Questions

Can I use essential oils to mask the smell?

No. While essential oils may temporarily cover odors, they don’t address the root cause and can leave oily residues that attract more dirt. Focus on eliminating bacteria instead of masking smells.

Is it safe to run cleaning cycles with vinegar regularly?

Yes, for most machines. White vinegar is non-corrosive and effective at breaking down mineral deposits and killing bacteria. However, avoid using it in machines with copper components, as prolonged exposure may degrade metal. Once a month is sufficient for routine maintenance.

Why does my new washing machine already smell?

Even brand-new machines can develop odors if stored in damp conditions before installation or if first uses involve cold water only. Run a hot vinegar cycle immediately after setup, and ensure the door remains open between uses.

Conclusion: Take Action Before the Smell Spreads

A washing machine that smells like sewage doesn’t mean replacement is necessary. In most cases, consistent cleaning and smart habits are all it takes to restore freshness. By incorporating monthly vinegar cycles, maintaining the door seal, and ensuring proper ventilation, you can prevent bacterial growth and extend the life of your appliance. Remember, the odor isn’t just unpleasant—it’s a warning sign of trapped moisture and potential mold. Address it early, and your clothes, machine, and home will stay cleaner and healthier.

💬 Have you fixed a smelly washing machine? Share your solution in the comments below—your tip could help someone avoid costly repairs!