Prep first
Before you start
- Rinse the surface with a damp sponge in cool water, then wipe it dry.
- Rub baking soda on a damp cloth over any film that remains.
- Rinse well so no cleaner is left behind.
- Test any cleaner on a hidden spot first.
Soap scum forms when soap reacts with the calcium and magnesium in hard water, leaving a film rather than a spill you can wipe up. On brick, concrete or stone it is especially stubborn, since it can be almost impossible to remove. A water softener is the long-term fix for the hardness that causes it.
Baking soda on a damp cloth is the method for glass, tile, grout, metal, fiberglass and acrylic, but test a hidden spot before using it on a finish you aren't sure about. Stubborn film that survives a couple of rounds is a sign to call a pro, not to scrub harder.
6 items
What you'll need
Tap an item to get it on Amazon, or tick what you already have.
- SpongeCarries cool water over the surface without spreading the film around. (opens Amazon)
- Baking sodaThe gentle cleaner for the film on hard, nonporous surfaces. (opens Amazon)
- Soft clothsOne damp for the baking soda, and one dry for the final buff. (opens Amazon)
- Bathroom cleaner in spray formOnly needed for glass shower doors, applied before any bleach solution. (opens Amazon)
- BleachFor the set-in step on bleach-safe, hard, nonporous tubs and showers only. (opens Amazon)
- Gloves (opens Amazon)
As an Amazon Associate we earn from qualifying purchases.
6 steps
Step by step
Step 1 of 6
Test a hidden spot first
Pick a spot nobody sees, such as the inside edge of a tub or the back of a door frame. Rub a little baking soda on a damp cloth there, rinse it, and let it dry before you judge the result.
Step 2 of 6
Rinse the surface with cool water
Dip a sponge in cool water and wipe the whole surface, working from the top down so loose film runs off instead of dripping onto clean areas. Rinse the sponge often so you aren't spreading the film around.
Step 3 of 6
Rub baking soda on a damp cloth
Dampen a cloth, sprinkle baking soda over it, and rub the film on glass, tile, grout, metal, fiberglass or acrylic. Work in small sections so the baking soda stays in contact with the film, and keep the cloth damp as you go.
Tip. A light rub does most of the work, so there's no need to scrub hard.
Careful. Do not use baking soda on aluminum, flat or matte painted walls, or fabric without testing first.
Step 4 of 6
Rinse until nothing feels slippery
Rinse the surface with clear water until the cloth comes away clean and nothing feels slippery or gritty under your fingers. Leftover cleaner needs to go, so don't stop at a quick wipe.
Step 5 of 6
Dry the surface with a soft cloth
Wipe the surface dry with a clean, soft cloth, buffing glass and metal until they shine. Check it in good light, since film is easiest to see once the surface is dry.
Step 6 of 6
Repeat only if film is left
If film remains, repeat the baking soda rub, then rinse and dry again. If it still won't lift after that, move to the stronger options in the set-in section.
If you'd rather buy than mix
Best products for soap scum
Pick a bathroom cleaner sold as a spray, and rinse it off fully before using any bleach solution.
Zep Concentrated Calcium, Lime and Rust Stain Remover
How we picked these: each product is made for this type of stain, its maker doesn't warn against using it on these surfaces, 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.
See what to do for what you're seeing →Heavy buildup usually takes more than one round.
Heavy or long-standing buildup →When to call a professional →Pick what it is on
Soap Scum on every material
Kitchen & bath5
Clothes & laundry1
Metal & glass1
Leather & suede1
Carpet & rugs1
Furniture & upholstery1
No match. Try the main search for anything else.
How to tell it's working
When the job is done, the film should look even, and the surface should feel smooth with no slippery or gritty patches under your fingers. A dull haze that stays after a full pass is more likely mineral build-up than soap film, so the set-in section is the next step.
What changes for yours
Adjust for where the stain is
Hard water
Soap scum is soap film, while hard water stains are mineral deposits, so they need the same routine but not the same expectations. The steps above clear the film, and a faint mineral haze may remain after a full pass.
In the long term, a water softener removes the hardness minerals that form soap film, so it is the real fix for a home with hard water. Until then, repeat the baking soda rub on the film and expect the haze to take more than one pass.
Glass shower doors
Glass shower doors take the same first pass as any hard surface, but the film there often sits alongside mildew. Start with the cool-water rinse and baking soda rub, and add a bathroom cleaner only if film stays.
The cleaner goes on as a spray and is rinsed off before anything else touches the glass. Keep it in its own pass, and never mix it with a bleach solution.
Brick, concrete and stone
Porous surfaces hold soap differently, so the baking soda steps don't apply here. Skip the rub entirely and go straight to the washing soda wash described in the set-in section.
No soap goes on these surfaces at any stage, and the routine ends with a rinse and a dry.
Tubs and showers
On a bathtub or shower wall, the steps work as written, and the rinse matters more than the scrub. Clean in sections from top to bottom, so loose film doesn't run back onto areas you have already finished.
Bleach is the last option here and belongs only on bleach-safe, hard, nonporous surfaces. Tubs that aren't bleach-safe should stay with the baking soda steps alone.
Heavy or long-standing buildup
Old soap scum that has built up for months needs more than one pass. Start by repeating the baking soda rub on a damp cloth, then rinse and dry again. Film that is still there after that is usually mineral build-up, so focus on the hard water rather than stronger cleaners.
On bleach-safe, hard, nonporous tubs and showers, mix 1/3 cup bleach into 1 gallon of cool water, wear gloves, and use it only after the film is off and the surface is rinsed. Rinse the bleach away fully as the last step. On glass shower doors, spray a bathroom cleaner, let it sit a few minutes, and rinse before any bleach solution of 4 teaspoons bleach in 4 cups water for mildew.
On porous brick, concrete or stone, scrub with a strong solution of washing soda or detergent, then rinse and dry. Expect to repeat the work rather than finish in one pass.
Vinegar, baking soda, peroxide and more
Do home remedies work on soap scum?
Only one of the remedies below is used in the steps. The others don't match this film, and some can damage common bathroom surfaces. If you want to avoid scrubbing and harsh chemicals, a damp cloth with baking soda is the gentlest option here, and it needs a light rub rather than hard scrubbing.
Works1Skip5
What makes it worse
Mistakes to avoid
Don't mix bleach with other cleaners
Never mix bleach with vinegar, ammonia, toilet bowl cleaners or acidic scale removers. Rinse the surface fully between products, and let bleach go on only as the last step.
Don't clean brick, concrete or stone with soap
Soap on porous surfaces builds up a scum that wiping won't remove. Reach for washing soda or detergent in the set-in section instead, since those are the options for brick, concrete and stone.
Don't skip the final rinse
Leftover cleaner can dull the surface and leave you with fresh film to deal with. Always finish with clear water, and don't stop until nothing feels slippery under your fingers.
Troubleshooting
If the stain is still there
Pick what you're seeing:
The film is still there after one baking soda pass
Repeat the baking soda on a damp cloth step, then rinse with clear water and dry. Test on a hidden spot first if you have not already.
The surface is brick, concrete or stone
Do not clean it with soap. Scrub with a strong solution of washing soda or detergent, then rinse and dry.
When to call a professional
If a full set-in pass still leaves film behind, or you are unsure what a porous stone surface can take, have a professional look before you try anything stronger. Don't risk damage to an expensive surface just to save a service call.
Questions
Do soap stains come out?
Yes, most soap film comes off hard surfaces with a cool-water rinse and a damp cloth with baking soda. Rinse well and dry, and expect a second pass on film that has built up for a long time. Porous brick, concrete and stone need a different approach.
Will a heat-based cleaner remove soap scum?
No, heat isn't needed for this film. Stick with baking soda, which is the safe choice for hard surfaces and doesn't rely on heat. They are the safe choice for hard surfaces, and they don't rely on heat.
How is soap scum different from hard water and calcium stains?
Soap scum is a film that forms when soap meets the minerals in hard water. Hard water and calcium stains are mineral deposits left when water dries, which is a different job. The steps here clear the film, and the mineral part needs the hard water routine.
Can I use bleach on soap scum?
Only on bleach-safe, hard, nonporous tubs and showers, and only after the film is off and rinsed. On glass shower doors, a bathroom cleaner goes on first and gets rinsed away before any bleach solution.
Is soap scum on brick, concrete or stone different?
Yes. Soap on porous surfaces builds a scum that wiping won't remove, so the routine changes. Use a strong solution of washing soda or detergent, then rinse and dry, and for a full routine on natural stone, see the Marble & Natural Stone guide.
Why does soap scum keep coming back?
Hard water keeps supplying the minerals that react with soap, so the film rebuilds unless the water changes. Clear it with the steps here, then treat the water as the root cause.
Related
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.