How to clean a mattress, including stains and smells

Step by step

1. 1

   Strip the bed and wash everything

   Take off the sheets, pillowcases and mattress protector and launder them according to their labels. If someone in the house has a dust mite allergy, wash bedding in hot water.

   Why: Bedding and protectors hold most of the sweat, skin flakes and allergens. NIEHS gives 130 to 140°F for killing dust mites; the AAAAI says 130°F and the American Lung Association at least 120°F.

2. 2

   Vacuum slowly, seams and edges included

   Go over the top, sides and edges with the upholstery attachment, working slowly. Pay attention to the seams and quilting, where dust and debris collect.

   Why: Dry soil comes off first. If you add liquid before vacuuming, you turn dust into mud and press it into the fabric.

3. 3

   Spot-clean with a damp cloth, not a spray

   Put a small amount of mild detergent solution, enzyme cleaner or oxygen bleach solution onto a white cloth, not onto the mattress. Dab and work the stain gently from the outside in, then blot with a cloth dampened in cold water to lift the cleaner out.

   Why: Foam and padding soak up liquid and hold it. Applying cleaner to the cloth keeps the moisture in the top layer where you can blot it back out.

4. 4

   Deodorize with baking soda

   Once the surface is dry, sprinkle baking soda over the whole mattress, leave it for several hours, then vacuum it up thoroughly.

   Why: Mattress makers suggest baking soda for absorbing odors. It works on a dry surface only; on a wet spot it turns into a paste.

5. 5

   Dry it completely

   Point a fan across any damp area, open windows or run a dehumidifier, and leave the bed unmade until the surface and the layers under it feel fully dry. Don't use a hair dryer or heater on stains.

   Why: Sheets on a damp mattress trap moisture, which leads to mildew, odor and new stains. Anything wet for more than 24 to 48 hours is at risk of mold.

6. 6

   Rotate and protect

   Rotate the mattress if the maker recommends it (most modern one-sided mattresses are rotated, not flipped), then put on a liquid-resistant protector before the sheets.

   Why: A protector is the main defense, because cleaning can't reach spills that have soaked deep.

What a mattress is made of, and what that rules out

Mattresses are all-foam (polyurethane, memory foam or latex), innerspring (coils under padding and fiber batting), or hybrids of the two. Most have a fixed fabric cover, called ticking, quilted to the comfort layers. Some foam models have a zip-off cover, but it usually isn't waterproof, and not all of them are washable.

That construction rules out a lot. No soaking, no pouring and no washing foam: one foam mattress maker says its comfort material should never get wet. No chlorine bleach, which damages polyurethane foam and many fabrics. No steam on memory foam, latex or adjustable mattresses, where heat and water can damage the materials and may void the warranty; some makers allow steam on innerspring and hybrid models only. And no heat on body-fluid stains, because heat sets protein.

How stains behave in a mattress, and the spot-treating rules

A spill goes through the thin ticking into the foam or batting, spreads sideways and down, and stays there. That's why a small accident can become a large water ring, a smell or mildew deep inside. Most mattress stains are body fluids, which are protein- and salt-based and set with heat.

The rules for every stain:

• Blot fresh spills at once with dry white towels, pressing to pull liquid up.
• Use the least liquid that works: dab and lift, never pour or saturate.
• Cold water for blood, urine and sweat. See blood on a mattress and sweat stains on a mattress.
• Clean with detergent or an enzyme cleaner, then blot with plain water to remove the residue.
• Dry fully before you make the bed.

How often to clean a mattress

Vacuum and spot-clean as needed, and wash sheets every week or two. One mattress maker suggests a full clean every six months and rotating every three to four months. For dust mite allergy, NIEHS and allergy groups recommend zippered allergen-proof encasements on mattresses and pillows, weekly hot washes of bedding, and keeping indoor humidity at or below 50 percent.

By situation

Pee on a mattress: stain and smell

Blot up as much as you can with dry towels, pressing hard. Then work an enzyme cleaner into the spot, following its label, and blot with a cloth dampened in cold water. Enzyme cleaners break down the compounds that cause urine odor instead of covering them with scent, and animal welfare groups recommend them for pet accidents. Keep steam and hot water away, which set urine stain and odor. Dry with a fan and repeat if the smell returns. Full steps are in urine on a mattress.

Blood on a mattress

Use cold water only: blot, then dab with a cold, slightly soapy cloth and blot again. On white ticking, 3% hydrogen peroxide dabbed on sparingly can lift what remains, but test it first because it can lighten colored fabric.

Yellow sweat stains and general discoloration

One mattress maker suggests an enzyme cleaner or hydrogen peroxide for sweat, urine or vomit stains, repeated as needed. Work in small patches and dry between rounds so the foam never gets soaked.

Getting a smell out of a mattress

Find and treat the source first: urine, sweat or a spill that soaked in. Then use baking soda on the dry surface for several hours, vacuum, and air the mattress with a fan or open windows. Avoid long direct sun: at least one maker excludes sun damage from its warranty. A musty smell after a spill means moisture is still inside.

Memory foam and latex mattresses

Treat them as dry-clean-only furniture: vacuum, spot-clean with a barely damp cloth, and never steam. If the cover zips off, check its label before washing; one maker's directions exclude dry cleaning, ironing and bleach.

A mattress soaked by floodwater or sewage

It usually can't be saved. Porous items that can't be cleaned and dried within 24 to 48 hours may need to be thrown away, and mattresses are seldom salvageable after water and mold damage.

What not to do

• Don't pour cleaner onto the mattress or soak it. Foam absorbs liquid and dries very slowly, which leads to rings, odor and mildew.
• Don't use hot water, steam, an iron or a hair dryer on blood, urine or sweat. Heat sets protein stains.
• Don't steam-clean memory foam, latex or adjustable mattresses. Heat and moisture can damage them and may void the warranty.
• Don't use chlorine bleach. It damages polyurethane foam and many fabrics.
• Don't make the bed while the mattress is damp. Bedding traps the moisture, and mold and mildew follow.

Other methods that work

Steam cleaning

Some makers allow it on innerspring and hybrid mattresses to freshen the surface.

Caution: Never on memory foam, latex or adjustable beds, never on fresh body-fluid stains, and only where the care guide allows it.

3% hydrogen peroxide

Used sparingly on a cloth, it can lift fresh blood and leftover color on white ticking.

Caution: It can lighten colored fabric. Test on a hidden area and don't saturate. More on hydrogen peroxide.

Professional cleaning

Worth it when a large amount of liquid has soaked deep, when a smell persists after drying, or when you're worried about the warranty.

Stain still there?

A water ring appeared around the spot I cleaned

Too much liquid spread through the ticking. Blot the edge with a barely damp cloth, feathering outward, then dry quickly with a fan.

The pee smell came back after it dried

Urine reached deeper than the cleaner did. Repeat the enzyme treatment, giving it the contact time on the label, then dry fully. For a large accident that soaked through, a professional may be needed.

The mattress smells musty

Moisture is trapped inside. Strip it, run a fan and dehumidifier, and keep it uncovered until it's dry right through. Persistent mustiness after a soaking can mean mold.

Safety

• Wear gloves when cleaning up blood, urine or vomit.
• Never mix bleach with ammonia or acids while cleaning bedroom spills.

Never mix cleaning products; see chemicals you must never combine.

Questions

Stains on a mattress

• Blood on a mattress
• Cat urine on a mattress
• Dog urine on a mattress
• Sweat on a mattress
• Urine on a mattress

More guides for this room

• How to clean a comforter or duvet at home
• How to clean pillows: washer, dryer, by hand and foam