How to Clean a Mattress: Stains, Smells and Upkeep

You change your sheets regularly, but the mattress underneath rarely gets attention. Over months and years it collects dust, dead skin cells, sweat, body oils and the occasional spill. A deep clean a couple of times a year keeps it fresher and helps it last longer. It takes a little time, mostly waiting, and you probably have everything you need already.

Check the care label first

Before you clean, look for the law label and any care tag on the mattress, and check the manufacturer’s website. Some brands give specific instructions, such as avoiding certain cleaners, limiting moisture or using only a particular spot-cleaning method. Following them also protects your warranty, since many warranties are voided by stains or water damage.

A few general rules apply to almost every mattress:

• Use as little liquid as possible. A mattress cannot be rinsed, and moisture trapped inside can lead to mildew and odors.

• Never soak it. Dab cleaners on with a cloth rather than pouring or spraying heavily.

• Test any cleaner on a hidden spot near the bottom edge first.

What you need

• A vacuum with an upholstery attachment and crevice tool

• Baking soda

• Clean white cloths or paper towels

• Mild liquid dish soap

• Cold water

• An enzyme cleaner made for pet or organic stains

• 3% hydrogen peroxide (for light-colored mattresses only, after testing)

• A spray bottle

Step 1: Strip and wash the bedding

Remove the sheets, pillowcases, mattress protector and any removable cover. Wash them according to their labels while you work on the mattress. If your mattress has a zip-off cover, check whether it is machine washable; many are not, and some covers are part of the fire barrier.

Step 2: Vacuum thoroughly

Vacuuming removes dust, skin flakes and debris from the surface. Use the upholstery attachment and work in overlapping rows across the whole top. Then use the crevice tool along the seams, edges and any tufts or buttons, where dust settles. Vacuum the sides, too.

Use a clean attachment, not one you just used on the floor.

Step 3: Spot-clean stains by type

Treat stains before deodorizing. Always blot, never rub. Rubbing pushes the stain deeper and roughs up the fabric.

Sweat and yellow body-oil stains

1. Mix a teaspoon of mild dish soap into a cup of cold water and stir up some suds.

2. Dip a cloth into the suds, not the water, and dab the stain.

3. Blot with a clean, damp cloth to lift the soap, then blot dry.

For older yellow stains on a light-colored mattress, a little 3% hydrogen peroxide dabbed on with a cloth can help. Test it first, because peroxide can lighten fabric.

Blood

Use cold water only. Hot water sets protein stains. Blot with a cold, damp cloth, then use the soap-suds method or an enzyme cleaner. Peroxide also works on blood but carries the same bleaching risk.

Urine (pets or kids)

1. Blot up as much liquid as you can right away, pressing firmly with dry towels.

2. Apply an enzyme cleaner according to the label. Enzymes break down the compounds in urine that cause lingering odor.

3. Blot, then let it dry completely before moving on.

Food and drink spills

Blot the spill, then use the dish soap suds method. For sugary drinks, follow with a cloth dampened in plain water to remove sticky residue.

Do not mix cleaning products on the same spot. In particular, never combine bleach with ammonia or vinegar. Chlorine bleach does not belong on a mattress at all.

Step 4: Deodorize with baking soda

Once any damp spots are dry, sprinkle a generous, even layer of baking soda over the entire top surface. Baking soda absorbs odors and some surface moisture.

Leave it as long as you can: several hours at minimum, and ideally all day. If the room gets sun, open the curtains. Then vacuum it up completely with the upholstery attachment, going slowly so you do not leave powder in the seams.

Step 5: Let it dry fully

This step is the one people rush, and it matters most. A mattress that goes back under sheets while still damp inside can develop mildew and a musty smell.

• Open windows or run a fan to keep air moving.

• Run a dehumidifier in humid weather.

• Press a dry paper towel onto treated spots. If it picks up any moisture, keep waiting.

• Allow several hours at least, and longer for thick foam or heavily treated areas.

Memory foam and latex cautions

Foam mattresses need a lighter touch than innerspring models.

• Keep moisture to a minimum. Foam acts like a sponge and dries slowly. Use barely damp cloths.

• Skip steam cleaners unless the manufacturer approves them. Heat and moisture can damage foam and adhesives.

• Do not use harsh solvents or strong chemicals, which can break down foam.

• Do not remove the cover to clean the foam unless the instructions say it is designed to come off.

Protect it going forward

Use a mattress protector. A washable, waterproof protector is the single best way to keep a mattress clean. It stops sweat, spills and accidents before they reach the mattress, and you can throw it in the wash. Wash it every month or two, or right after a spill.

Rotate it. Many mattresses should be rotated head to foot every three to six months so wear is even. Only flip it if the manufacturer says it is two-sided; many modern mattresses have layers designed to face up only.

Air it out. When you change the sheets, leave the bed stripped for an hour so moisture can escape.

How often should you clean a mattress?

Vacuum it every time you rotate it, or every few months. Do a full clean with deodorizing every six months, and treat spills and accidents right away. Households with pets, allergies or young children may want to clean more often.

FAQ

Can I use a carpet cleaner on my mattress?

It is usually not a good idea. Carpet machines put a lot of water into the material, and a mattress cannot dry the way a thin carpet does. Stick to spot cleaning unless the manufacturer says otherwise.

How long should baking soda sit on a mattress?

At least a few hours, and up to a full day for stronger odors. Vacuum it all off before making the bed.

What gets old urine smell out of a mattress?

An enzyme cleaner works best because it breaks down the source of the odor rather than masking it. You may need to repeat it once or twice, letting the mattress dry fully each time.

When is a mattress beyond cleaning?

If it has mold, a persistent smell after repeated cleaning, sagging or visible damage, replacement is usually the healthier choice.

Quick recap

• Read the care label and manufacturer instructions first.

• Strip and wash the bedding, then vacuum the mattress and its seams.

• Blot stains with the right method: cold water for blood, enzyme cleaner for urine, soap suds for sweat.

• Deodorize with baking soda for several hours, then vacuum.

• Let it dry fully before making the bed, and go easy on moisture with foam.

• Use a washable protector and rotate the mattress every few months.