Prep first
Before you start
- Brush or vacuum dry mildew and soot before anything gets wet.
- Keep liquid to a minimum and don't soak the mattress.
- Test any cleaner on a hidden spot first.
- Work out the cause before you pick a method.
Dark stains on a mattress are often mildew, but soot or real damage can look identical, and the cause decides how much you can lift. Loose growth comes off first, outdoors with a soft broom and then a vacuum, so you aren't working spores into the padding. Old marks that have soaked deep may only lighten, and a damp mattress needs drying before anything else.
Go easy with liquid on a mattress, and blot a little at a time rather than soaking the top. Dark brown stains on a mattress need extra patience, since memory foam holds moisture for a long time. If a dark stain on a mattress comes back after it's fully dry, call a professional before you scrub harder.
Before you start
What mattress can take
Use with care4
- Water
- Oxygen bleach
- Enzyme cleaners
- Acids (vinegar, lemon)
Avoid4
- Hot water
- Soaking
- Chlorine bleach
- Solvents (alcohol, spot removers)
6 items
What you'll need
Tap an item to get it on Amazon, or tick what you already have.
- Soft-bristled broomLifts loose mold spores off the surface before anything gets wet.
- Vacuum with an attachmentDraws out more mold from the surface. (opens Amazon)
- Electric fan and electric heaterDries a damp mattress by warming the air and carrying the moisture away. (opens Amazon)
- Mild liquid dish soapMakes the cold-water soap wash that lifts the stain. (opens Amazon)
- Sponge and clean clothsApply the solution lightly and blot it back up. (opens Amazon)
- Fungicide sprayHelps get rid of mildew once the mattress is clean and dry.
As an Amazon Associate we earn from qualifying purchases.
5 steps
Step by step
Step 1 of 5
Brush off the loose mold outdoors
Work a soft-bristled broom over the mattress surface to lift loose mold spores. Do this outdoors if you can, so the spores don't scatter through the house. Wash the broom before you use it again.
Step 2 of 5
Vacuum the surface thoroughly
Run a vacuum attachment over the whole mattress surface to pull out more mold. A disposable bag should be thrown away right away, and a reusable one should be emptied carefully, preferably outdoors.
Careful. Don't empty a full bag indoors, because the spores escape into the air.
Step 3 of 5
Dry any damp areas quickly
If the mattress is moist or damp, run an electric fan and an electric heater over it. The heater warms the air and the fan carries the moisture away.
Step 4 of 5
Wash the stain with mild soap
Mix 1 teaspoon of mild liquid dish soap into 1 cup of cold water. Dampen a sponge with the solution, dab the stain lightly, and blot as you go, moving from the edges toward the middle. Use only enough liquid to dampen the area.
Tip. Blot with a dry cloth as you go so the soap doesn't sit in the fabric.
Careful. Excess moisture can break down memory foam, so keep the liquid to a minimum.
Step 5 of 5
Let the mattress dry fully
Blot the area thoroughly, then leave the mattress to dry in direct sunlight and fresh air if you can. Check the stain only once the spot is fully dry, so you judge the real result.
If you'd rather buy than mix
Best products for black stains on mattress
Once the mattress is clean and fully dry, a low-pressure spray with a fungicide helps get rid of mildew. Respray often if mildew is a problem in your home.
Rug Doctor Spot & Upholstery Cleaner
BISSELL Little Green Portable Carpet & Upholstery Cleaner
Utopia Kitchen White Flour Sack Towels
Empty Spray Bottles 16oz/4Pack
How we picked these: each product is made for this type of stain, its maker doesn't warn against using it on mattress, and its directions fit the steps above.
Finished the steps? How does it look?
Nice work. Let it dry completely and check it again in good light before using any heat. Here is what done looks like:
How to tell it's really gone →A faint mark usually needs one more round, not a stronger product.
Heavy buildup usually takes more than one round.
Heavy or long-standing buildup →When to call a professional →How to tell it's working
Dark color should lift onto your cloth with each blot, and the patch should read lighter when it's fully dry instead of while it's still damp. If it stays dark after two rounds, the mark has set, so switch to the set-in section.
What changes for yours
Adjust for your mattress
Dark brown marks on a mattress
Brown marks often sit deeper in the ticking, so use the lightest touch you can. Dampen the sponge rather than the mattress, and blot the soap solution in a small area that doesn't spread.
Keep the sequence the same, but expect that a faint brown shadow may remain after the soap wash. If it stays once the area is fully dry, move to the set-in options rather than adding more liquid to the same spot.
Memory foam mattress
Memory foam suffers most from moisture, so it needs the lightest treatment of any surface here. Work with a sponge that's barely damp, and keep the liquid from running into the foam.
Give the mattress extra time under the fan, and feel the middle as well as the surface before you call it dry.
Foundation or box spring
The base under the mattress needs the same care, so keep liquid off it. Keep your work to the top surface, and don't let the sponge drip down the sides.
If the mark has crossed onto the foundation, use only dry brushing and a barely damp sponge there, then let it dry in the sun and air.
Colored ticking
Colored ticking can lose dye when it's wet, so pretest every cleaner on a hidden spot before using it on the stain. Use the soap wash on that test spot first and look for color on the cloth.
If the test spot changes color, stop, because the cleaner isn't safe for that fabric.
Mildew in a damp room
A damp room keeps the mattress damp, so mildew can return even after a good clean. Run the fan and heater and let air move through the room while the mattress dries.
Respray with a low-pressure fungicide spray often if mildew has been a problem in your home, and check the spot after each spray.
Heavy or long-standing buildup
An old stain that has dried is harder, so give it one more pass rather than a heavy soak. Repeat the mild soap wash once, lightly, with a cloth that's only damp. Let the area dry in the sun and air before you judge the result.
If the mark is still visible once the area is fully dry, an upholstery cleaner made for fabric is the next option. Pretest it on a hidden spot and follow the directions on the bottle.
Set realistic expectations, because a faint shadow may stay, especially on an older stain. If mold has gone deep into the padding, surface cleaning won't reach it, and porous materials that are moldy may have to be thrown out.
Vinegar, baking soda, peroxide and more
Do home remedies work on black stains on mattress?
A few common household remedies come up for black marks on a mattress, but most of them don't belong here. Hold the few that might help in reserve for a stubborn spot.
Works1Skip4Avoid1
What makes it worse
Mistakes to avoid
Don't paint over mildew
Covering the mark hides it while the mildew keeps growing, so the stain comes back. Clean and dry the area fully first, then judge what's left.
Don't treat every black mark as mildew
Black can also be soot, manganese, rubber or damage to the fabric. Check the smell, the feel and how the mark appeared before you pick a method.
Don't sweep the mold back into the room
Brushing loose growth indoors sends spores into the air and onto nearby surfaces. Do it outside, and wash the broom before you use it again.
Don't empty the vacuum canister indoors
Spores collect in the vacuum, and dumping them inside puts them right back where you were cleaning. Bin a disposable bag straight away, and empty a bagless canister carefully outside.
Don't dry a damp mattress with a fan alone
An electric fan and an electric heater work together, with the heat and moving air carrying the moisture out of the mattress. Direct sun and fresh air help stop mold from getting going again.
When to call a professional
An upholstery cleaner is the next step when the mark survives the wash and the set-in section, especially if it's wide or has gone deep into the padding. If the growth covers more than 10 square feet, follow the official remediation guidance rather than spot cleaning. Give them the age of the mark and any product that's already touched it.
Questions
Is the black on my mattress mold or dirt?
It can be mildew, soot, manganese or damage, so the cause isn't always clear from color alone. Look at the smell and feel, and think about whether dampness came first. Start with the brushing and vacuuming step, then see what's left before you choose a cleaner.
Can I dry a damp mattress with a fan and heater?
Yes, and that's the way to go when the mattress is moist or damp. The heater warms the air and the fan carries the moisture away, which helps the mattress dry out.
Will the black mark come out completely?
Often it fades a lot, but not every black mark comes out. Some marks are damage rather than dirt, and an old stain that has soaked in can leave a faint shadow. The set-in section covers what to try next.
Does sunlight help with mold on a mattress?
Yes. Direct sunlight and fresh air help stop mold growth, so use them whenever you can put the mattress outside. Let it dry fully, then check the spot again before you try anything stronger.
Why does the black stain keep coming back?
Mildew keeps growing while the area stays damp, so a stain that returns usually means the moisture never fully dried. Dry the mattress all the way through, then respray with a fungicide spray if mildew is a problem in your home.
Can I take the mattress cover off and wash it?
Check the care label first, since some covers are sewn shut and aren't meant to come off. Where a cover can be removed, wash it only as the label allows, because taking it off may cancel the mattress warranty.
How do I get a smell out of a mattress?
Baking soda works on odor once the spot is dry: a light dusting can sit for around 20 minutes, or for as long as five hours when the smell is strong, before you vacuum it up. Open the windows while it sits so the room airs out too.
Can I use bleach on a black mark on my mattress?
No. Bleach can damage the mattress fibers, so it's off the table even for a stubborn mark.
Never mix it with ammonia, vinegar, rubbing alcohol or other cleaners either. If the spot won't lift, an upholstery cleaner is the safer next step.
Black Stains on other materials
Other stains on mattress
Start from the bigger picture
How we know this
Every method, amount and warning here comes from university extension services, industry bodies and product makers. We read them, check every step for unsafe combinations and changed amounts, and write it up so you can follow it.