How To Get Mildew Smell Out Of Mattress: Simple Steps That Actually Help

If you’re searching for “How To Get Mildew Smell Out Of Mattress,” you’re likely dealing with a mattress that’s been damp, stored poorly, or exposed to humidity. This guide walks through why that smell appears, how to handle it safely, and what you can realistically do to reduce or remove it.

What Causes a Mildew Smell in a Mattress?

A mildew smell usually means moisture has been trapped inside the mattress. Mildew and other odor-causing microbes thrive in:

Spills that weren’t fully dried
High humidity or poor ventilation
Mattresses placed directly on the floor
Long-term storage in damp spaces

The odor can linger even after the surface feels dry because the core materials can still hold moisture.

First Step: Is It Safe to Try to Save This Mattress?

Before focusing on how to get mildew smell out of mattress, check whether the mattress may be too compromised to keep.

Ask yourself:

Is there visible mold or fuzzy growth?
Is the smell strong and musty even after airing it out?
Was the mattress soaked deeply (flooding, heavy leak, long-term damp)?

If you see extensive mold growth or the mattress was heavily saturated for a long time, many people choose to replace it rather than try to restore it. Surface-level odors from light moisture or small spills are more realistic to address at home.

Step-by-Step: How To Get Mildew Smell Out Of Mattress

1. Air It Out Thoroughly

Getting rid of odor starts with drying and ventilation.

Remove all bedding, mattress protectors, and toppers.
Place the mattress in a well-ventilated room or near open windows.
If possible, stand it on its side so air can circulate around it.
Use fans to blow air across the surface and a dehumidifier to reduce moisture in the room.

Allow several hours, or longer if the mattress recently got damp.

2. Surface Clean the Affected Area

Once you’re sure the mattress is dry to the touch, gently clean where the smell is strongest.

Vacuum the mattress (top, sides, and seams) using an upholstery attachment to remove dust and loose particles.
Mix a mild cleaning solution: a small amount of gentle liquid soap in warm water.
Lightly dampen (not soak) a clean cloth in the solution and blot the surface. Avoid saturating the foam or inner materials.
Follow with a cloth dampened in plain water to remove any soap residue.

The goal is light surface cleaning, not deep soaking.

3. Use Baking Soda to Help Neutralize Odors

Baking soda is commonly used to absorb and help neutralize smells.

Sprinkle a generous, even layer of baking soda over the entire mattress surface, focusing on the smelliest areas.
Gently rub it in with a soft brush or your hand.
Leave it for several hours or, if possible, a full day.
Vacuum up all the baking soda thoroughly.

Many sleepers repeat this once or twice if the mildew odor is still noticeable.

4. Consider a Light Vinegar Mist (With Caution)

Some people use white vinegar as an odor-fighting household cleaner. If you choose to try this:

Mix equal parts white vinegar and water in a clean spray bottle.
Lightly mist the affected area; do not soak the mattress.
Allow the mattress to air dry completely in a well-ventilated space.
Once dry, you can apply baking soda again to help with any remaining smell.

Vinegar has its own scent at first, but it often fades as it dries.

5. Dry, Dry, and Dry Again

For any approach to work, the mattress must stay very dry afterward.

Keep the mattress in a dry, airy room while it finishes drying.
Use fans or a dehumidifier if your space is naturally humid.
Avoid putting on mattress protectors or bedding until the mattress feels completely dry.

Trapped moisture is one of the main reasons mildew smells return.

How Long Does It Take for a Mildew Smell to Go Away?

The timeline varies:

Mild odor, small damp spot: Sometimes a day or two of airing and baking soda treatment is enough.
More stubborn smells: You may need to repeat the treatments over several days and keep the room dry and ventilated.

If the smell remains strong after multiple attempts, it may be coming from deeper inside the mattress where home cleaning cannot reach effectively.

Can You Sleep on a Mattress That Still Smells Like Mildew?

Many people prefer to wait until the smell is significantly reduced or gone before sleeping on the mattress again. If the odor returns quickly after cleaning, or intensifies when the room is closed up, it may be a sign that moisture is still trapped inside.

In that case, consider:

Whether the mattress has aged or broken down
If there was a major water event (leak, flood, long-term dampness)
Whether a replacement might be more practical than repeated treatments

How To Prevent Mildew Smell From Coming Back

Once you’ve worked through how to get mildew smell out of mattress, prevention becomes key.

Use a water-resistant, breathable mattress protector.
Keep the mattress on a proper bed frame (not directly on the floor) to allow airflow underneath.
Air your mattress occasionally by removing bedding and opening windows.
Address spills right away: blot, clean, and dry thoroughly.
Avoid storing mattresses in damp basements, garages, or outdoors.

✅ Quick Mattress Takeaways

Key points consumers should understand about How To Get Mildew Smell Out Of Mattress

Check severity first: Strong, persistent odor and visible mold can indicate a mattress that may not be worth saving.
Drying is essential: You can’t get rid of mildew smell if the mattress is even slightly damp inside.
Gentle cleaning only: Light surface cleaning, baking soda, and cautious vinegar misting are common home approaches.
Be patient and repeat as needed: Odor reduction can take several rounds of treatment and extended ventilation.
Focus on prevention: Good airflow, quick spill cleanup, and protective covers help stop mildew smells from developing again.

With time, careful drying, and consistent odor-control steps, many mattresses with minor mildew smells can become much more comfortable and fresher to use.