A washing machine is meant to make your clothes clean and fresh—but when the appliance itself starts to smell bad, it can turn laundry day into an unpleasant chore. If you’ve opened the washer door or lifted the lid only to be hit with a musty, sour, or moldy odor, you’re not alone. Washing machine smells are a common issue in many households, and the root cause is usually a combination of moisture, detergent residue, and hidden grime. The good news is that with a little time and effort, you can eliminate those odors and keep your washer smelling clean.

The most frequent culprit behind unpleasant smells in washing machines is mold and mildew. These thrive in warm, damp, and dark environments—exactly what the inside of a washing machine offers, especially when it’s left closed between cycles. The rubber door seal on front-loading machines is particularly vulnerable, often collecting water, hair, lint, and detergent residue in its folds. Over time, this gunk becomes the perfect breeding ground for bacteria and mold, which produce that musty smell.

Even top-loading machines aren’t immune. While they may not have the same rubber gasket as front-loaders, the inner components—like the tub, agitator, and detergent dispenser—can still harbor buildup. If you use too much detergent or wash primarily with cold water, soap residue can cling to the inner walls and accumulate with every load. This residue mixes with body oils, dirt, and fabric fibers, creating a biofilm that traps bacteria and causes a sour or rotten odor over time.

One of the simplest ways to prevent and eliminate washing machine odors is to clean your machine regularly. For both front-load and top-load washers, run a cleaning cycle using hot water, 1 cup of white vinegar, and ½ cup of baking soda. Vinegar helps break down mineral deposits and mildew, while baking soda deodorizes and lifts grime. Let the washer fill with hot water (or set it to the hottest cycle), pause the cycle for an hour to let the solution soak, and then complete the wash. Afterward, wipe down all accessible surfaces with a microfiber cloth, including the drum, rubber seals, door, and detergent compartments.

Commercial washing machine cleaners are another option, especially those designed to break down biofilm and eliminate odor-causing bacteria. These tablets or liquids are easy to use. Add one to an empty machine and run a hot cycle. For stubborn smells, repeat the process several times or once a week until the odor fades. Then, maintain freshness by using a cleaner once a month as part of your regular laundry routine.

Cleaning the detergent drawer is just as important. This often-overlooked area can harbor mold and soap scum. Most detergent drawers can be removed entirely for thorough cleaning. Use a small brush or an old toothbrush to scrub the inside of the compartment and the area behind it. Rinse everything thoroughly, and allow it to dry before replacing it. Don’t forget to clean the bleach and fabric softener compartments as well, since residues can also build up there.

Airflow is another critical factor in preventing washing machine odors. One of the biggest mistakes people make is closing the washer door or lid immediately after use. Doing so traps moisture inside the drum and rubber seals, creating a humid environment perfect for mold growth. Instead, always leave the door slightly open after each wash to allow fresh air to circulate and dry out any lingering moisture. If you live in a humid climate or have limited ventilation in your laundry room, consider using a small fan or dehumidifier nearby to help speed up drying.

It’s also worth reviewing how much detergent you’re using. More soap doesn’t equal cleaner clothes—in fact, it can lead to the opposite. Excess detergent can leave behind residue that collects dirt and feeds bacteria. Always follow the manufacturer’s recommendations, especially if you have a high-efficiency (HE) washing machine, which uses less water and requires specially formulated low-sudsing detergent. Using too much soap in an HE washer can lead to buildup, odors, and even mechanical issues over time.

If your washing machine has a drain pump filter, that’s another place to check. Located near the bottom of the machine, behind a small panel, the drain pump filter catches lint, hair, and small items such as coins or buttons. If it becomes clogged, it can cause standing water, poor drainage, and foul smells. Carefully remove the filter according to the manufacturer’s instructions, clean out any debris, and rinse it under warm water before reinserting it. Be sure to place a towel or shallow pan underneath to catch any residual water that may spill out during the process.

Some washing machines also have hidden crevices and hard-to-reach areas where buildup can collect. For these spots, using a steam cleaner or detailing brush can help dislodge gunk and refresh the interior. If your washer has a self-cleaning cycle, use it regularly as directed. These cycles are designed to flush out buildup and maintain internal cleanliness with high heat and water pressure.

Another effective method for maintaining long-term freshness is incorporating essential oils into your cleaning process. After deep cleaning the washer, add a few drops of tea tree oil or lemon oil to a cloth and wipe down the drum and door seal. These oils have natural antimicrobial properties and leave a pleasant scent. Be cautious not to add essential oils directly to the washer during a cycle, as they can damage plastic parts if misused.

Sometimes, persistent smells may stem from your water supply. If you’re on healthy water or your municipal water has a high mineral content, those minerals can interact with soap to create a sour smell. Installing a water softener or using vinegar regularly in the rinse cycle can help minimize these effects. Similarly, if your washing machine drains into a clogged or poorly vented plumbing line, foul odors from the drain can creep back up into the appliance. A plumber can inspect the drainage system to ensure proper flow and venting.

In households with frequent laundry use—especially those with young children, athletes, or pets—odor issues are more common simply due to the higher load of sweat, dirt, and bacteria entering the machine. In these cases, increasing the frequency of your washer cleanings, switching to odor-fighting detergents, and occasionally using hot water cycles can all help manage the load.

A smelly washing machine doesn’t mean you need a new appliance, but it does mean your current one needs some attention. Most odors are the result of moisture, residue, and neglect all of which are easy to remedy with the right steps. Regular cleaning, proper detergent use, and attention to drying and airflow will help keep your washer smelling fresh and functioning correctly. By incorporating a few simple habits into your laundry routine, you can eliminate unpleasant odors and enjoy clean, fresh laundry—just the way it should be.