Prep first
Before you start
- Find the cause first: location, smell, feel and how the mark appeared all point to the right treatment.
- Test any cleaner on a hidden spot before you use it on the visible mark.
- Brush off dry soot and mildew before you add any water.
Black marks on plastic come from mildew, soot, manganese from well water, rubber from heels and tires, or greasy residue, and each one needs a different approach. Abrasive scrubbing is ruled out on plastic, so start with the gentlest cleaning and work up only if needed. Some black marks are damage rather than dirt, and a mark that has set in may not come out fully.
Black stains on a plastic cutting board often lift with a paste of baking soda, but test a hidden corner first. Black marks on an AirPods case or phone case need only a damp cloth, and plastic food containers can take a longer soak. If a mark won't move after a couple of soaks, stop there and don't reach for anything stiffer.
Before you start
What plastic & tupperware can take
Safe to use1
- Water
Use with care2
- Hot water
- Solvents (alcohol, spot removers)
Avoid2
- Scrubbing and abrasives
- Heat, once the stain is out
9 items
What you'll need
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- Small brushClears dry debris and gently works the paste into the mark. (opens Amazon)
- Clean clothsFor wiping on the washing solutions and drying the plastic.
- Mild soapMakes the first wash on any plastic, including silicone cases. (opens Amazon)
- White vinegarFor the light mildew mix. (opens Amazon)
- Washing soda (opens Amazon)
- Baking sodaFor the heavy mildew paste, used last. (opens Amazon)
- Chlorine bleach (opens Amazon)
- Commercial mildew stain removerReach for the bleach paste only as a last resort, once the ammonia wash and the vinegar wash haven't lifted the mark, and rinse well before you switch. (opens Amazon)
- Clear household ammonia (opens Amazon)
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6 steps
Step by step
Step 1 of 6
Brush off dry soot and mildew
Find out what made the mark before you pick a method. Location, smell, feel and how it appeared all point to mildew, soot or grease.
Brush or vacuum any dry soot or mildew off first, since wetting it spreads it across the plastic. If the item has mildew, do the brushing outdoors.
Step 2 of 6
Test a hidden spot first
Choose a spot nobody sees, such as the underside of a lid or the back of a case. Apply the cleaner there, let it dry, and check for any change in color or a dull patch.
Only move on to the visible mark once the hidden spot looks the same as before.
Careful. Skipping the hidden-spot test can leave a discolored patch on the plastic.
Step 3 of 6
Wash with warm sudsy ammonia water
Dip a cloth in warm sudsy water with a few drops of ammonia added, and wipe the stain in firm passes. Keep turning to fresh areas of the cloth until it stops picking up black.
Work the whole stained area, not just the darkest spot, so the mark doesn't look patchy when it dries.
Careful. Ammonia isn't safe on silicone phone cases, so use mild soap and water there.
Step 4 of 6
Rinse well and wipe dry
Rinse the area with clear water until no suds or residue remain. Wipe the plastic dry with a clean cloth and check the mark in good light.
If the mark is still there, the vinegar mix is the next step.
Step 5 of 6
Treat light mildew with the vinegar mix
For light mildew, mix 1/2 cup white vinegar, 1/4 cup washing soda and 1 gallon warm water. Wipe the mix over the stain, let it work briefly, then rinse thoroughly with clear water.
Dry the plastic fully before you judge the result, because a damp surface can look darker than it will be.
Step 6 of 6
Scrub heavy mildew with bleach paste last
Use this only if the mark survived the lighter steps. Mix baking soda with chlorine bleach into a paste, then scrub the stain gently with a small brush.
Rinse until no bleach smell remains, and dry the plastic before you check the result.
Careful. Chlorine bleach can intensify manganese or iron stains, so rule those out first.
If you'd rather buy than mix
Best products for black stains on plastic & tupperware
Look for a commercial mildew stain remover and follow its container directions, and pretest it on a hidden spot first.
Amazon Basics Microfiber Cleaning Cloths
How we picked these: each product is made for this type of stain, its maker doesn't warn against using it on plastic & tupperware, 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. 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
A clean patch looks even in color, with no dark speckles, and it doesn't carry a musty smell. If the mark is fainter but still visible after a full rinse and dry, look again before you repeat a step.
What changes for yours
Adjust for your plastic & tupperware
AirPods case
The case is small, so work with a cloth that's only slightly damp and keep liquid away from the openings. Wipe the outside with mild soap and warm water on a soft, lint-free cloth, and don't spray anything onto the case.
Skip hydrogen peroxide here, since electronics like this are on its unsafe list. If the mark stays after one gentle wipe, repeat the mild soap wipe rather than moving to a harsher product.
Phone case
If the case is silicone or rubber, use mild soap and warm water only. Window cleaners, household cleaners, aerosol sprays, solvents and abrasives are all off-limits on silicone, so leave them off the list.
If you're not sure of the material, treat it as silicone and stick to the mild soap. Wipe, rinse and dry the case fully before you put it back on the phone. Hard plastic cases can follow the washing steps above, after a test on a hidden spot.
Plastic food containers
Hand wash the container in hot soapy water, which plastic can take, and wipe the lid separately. If a marker-type mark sits on a lid, the washing steps are as far as you should go, and solvents stay off the plastic.
If the mark is still there after washing, use the vinegar mix first and save the heavy-mildew paste for the end. Let the container dry fully before you put it away or reuse it, so no damp spots are left behind.
Plastic bathtub
Start with the mild soap and warm water wash, then the vinegar mix for mildew, since plastic tubs can take both. If the tub is acrylic, leave solvents and alcohol out completely.
Mildew keeps growing if the area stays damp, so dry the tub after each rinse. For the full tub method, see the Bathtubs guide.
Plastic shoes
Plastic shoes don't have a dedicated treatment, so test mild soap and warm water on a hidden spot first. Stay with the light steps, and skip bleach unless you've tested a hidden spot first.
Keep solvents off the shoe, and keep the wash gentle. For the full shoe method, see the Shoes & Sneakers guide.
Heavy or long-standing buildup
If the mark has been there a long time, the first wash may only lighten it, so repeat the washing step before you move on. Old mildew that has dried into the plastic may need the bleach paste as the last step, but only after you've checked the cause.
Dried-on marks often need the washing steps repeated rather than a stronger product. Repeat the wash only on plastic that has already passed the hidden-spot test, and stop if the surface starts to look dull.
If the mark is still there after that, a commercial mildew stain remover used according to the package directions is the next option. Some black marks can't be fully removed, so accept a faint shadow rather than reaching for harsher products.
Vinegar, baking soda, peroxide and more
Do home remedies work on black stains on plastic & tupperware?
Plenty of household remedies come up for black marks, but most were written for fabric or other surfaces. Warm sudsy water with a few drops of ammonia does most of the work on plastic, with the rest kept for stubborn mildew.
Works2Skip2Avoid2
Chemical safety
Never mix these
Some products in this guide react dangerously with each other. Use them one at a time and rinse with water in between.
Chlorine bleach + Vinegar
Vinegar is an acid, and acid mixed with bleach gives off toxic chlorine gas.
Ammonia + Vinegar
Poison Control warns that mixing ammonia products with other cleaners is dangerous, and the ammonia maker's safety sheet lists acids such as vinegar as incompatible.
Ammonia + Chlorine bleach
Bleach mixed with ammonia releases toxic chloramine gas.
Ammonia + Baking soda
The ammonia maker's safety sheet says not to mix ammonia with other household chemicals, and Poison Control warns against mixing ammonia products with other cleaners.
If they mix by accident: Stop and add nothing else; leave the area for fresh air, open windows and keep children and pets away; call Poison Control at 1-800-222-1222, or 911 if anyone has trouble breathing.
What makes it worse
Mistakes to avoid
Don't use abrasive cleansers or scrub pads
Abrasive cleansers and scrub pads are off the list for plastic, whatever the stain. If the mark needs more work, repeat the wash rather than scrubbing harder.
Don't put plastic lids on or near a flame or heat
Plastic lids and containers can warp or blister with direct heat, so keep them away from the stovetop, broiler and oven. Extreme heat, such as a hot car, is off-limits for glasses too.
Don't microwave with lids sealed
Lids sealed tight can warp in the microwave. Vent them or set them offset before you heat anything.
Don't overheat fatty or sugary food in plastic
High-fat foods, sugar, oils and tomato sauce can stain and blister plastic when they get too hot. Let containers cool and wash them soon after use, so residue doesn't bake on.
When to call a professional
If the mark is still there after the washing steps and the set-in options, stop before trying anything harsher, since the wrong product can dull or warp plastic. A cracked, warped or deeply stained piece is usually easier to replace than to restore.
Questions
Does vinegar remove black mildew from plastic?
For light mildew, yes. The vinegar mix is the first chemical step after the wash, and it works best on a surface that's already been brushed clean. Heavy mildew usually needs the bleach paste as the last step.
How do I tell mildew from soot on plastic?
Look at where the mark sits and how it appeared. Mildew tends to show up in damp spots and can smell musty, while soot is dry and brushes or vacuums off more easily.
Can I wash plastic food containers in hot water?
Yes, hand washing in hot soapy water is the plastic-safe way to do it. Let the container dry fully before you store it.
Will black marks come out of a plastic bathtub?
Often they do, if the mark is mildew or grime and you treat it with the washing steps first. Old damp marks may leave a faint shadow that can't be fully removed.
Can I use hydrogen peroxide on AirPods?
No. Electronics like AirPods are on the unsafe list for hydrogen peroxide, so keep it away from the case. Mild soap and a lightly damp cloth are the safer choice.
Can I use rubbing alcohol on a plastic phone case?
No. Alcohol and other solvents aren't a safe choice for these cases, and silicone can't take them at all. Mild soap and warm water is the safer way to clean a phone case.
Is bleach safe on plastic shoes?
Not without a test first. Start with mild soap and warm water on a hidden spot, and only use bleach if that spot looks unchanged.
How do I keep black marks from coming back on a cutting board?
Dry the board fully after every wash, and don't leave it damp. Keep it away from direct heat, which can warp or blister plastic.
Black Stains on other materials
Other stains on plastic & tupperware
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.