The 10 Best Mold and Mildew Cleaners

If you want the best overall cleaner on the market, look to Star Brite. This is a bleach-based formula which means it’s definitely powerful. Bleach is just highly effective at killing mold and mildew. But that means you’ll need to take the proper precautions. Make sure you use this in a well ventilated area. Also, avoid other cleaners. You never want to mix a bleach based cleaner with ammonia. The fumes it produces are toxic. In an enclosed space they could overwhelm you right away. Make sure you’re using gloves as well to protect your skin.

What separates Star Brite from just a bottle of bleach is the formula. This is bleach based but not just bleach. They use what is called a buffeted formulation. That means it’s been designed to be less hard on surfaces. You can safely use this on your vinyl and even the stitching. It’s been designed to not weaken your stitching, which is very helpful. That said, it’s not recommended for use on fabric. You’ll want to avoid getting this on your clothes.

Star Brite is very easy to use and versatile. This is a spray and wait formula. In a serious case you may still need to scrub. But try just spraying and letting it work at first. Give it a good amount of time to soak in. Then use your sponge to wipe it away and see how it looks.

The formula is safe for most surfaces on your boat. Fiberglass, vinyl, even painted surfaces and rubber. We recommend you saturate the area and wait ten minutes for it to soak in. Then, when it’s done, spray the area clean first. If you still have stubborn stains, reapply the cleaner. Then, on this second pass, try scrubbing to finish the job. Then spray it clean again. Stubborn mildew stains should now gone by then.

Just remember, the smell can be intense. If you’re cleaning down around your bilge or in a tight space, keep those vents open. Take regular breaks, too. If you’re feeling light headed, give yourself a few minutes. That goes for any cleaner on our list. Don’t make yourself sick just to cut through some mildew.

One thing to remember about Star Brite is that it doesn’t prevent mildew. Once you clean up, you should apply another product to treat your surfaces and prevent new mildew.

Star Brite is one of the more affordable options you’ll find. Combine that with the fact it’s also one of the most powerful and this should really be your first choice for most mildew cleaning.

Marine Spray Nine Heavy Duty is a tough product. This is an ammonia based cleaner and it is not messing around. There’s a reason so many boating magazines and others have ranked it number one. It’s powerful and it’s effective. The price is also pretty reasonable.

It’s not just mold and mildew this product can eliminate. It’s also an effective degreaser and disinfectant. In fact, in addition to killing a couple of kinds of fungus, this makes short work of many other harmful things. For instance, let it sit on a surface for just 45 seconds. When it’s done you will have effectively killed 14 kinds of dangerous bacteria. That includes, e.coli, salmonella, staph and strep, listeria and bordetella.

In just 30 seconds this formula will also destroy over 15 kinds of viruses. That is including flu strains.If you want something as clean as it can possibly get. Spray Nine has your back.

The formulation is an ideal stain remover for boat seats. It’s also great on several hard surfaces as well. You can clean up everything from your hull to your life jackets with this.

For most stains the process is very simple. Spray it on and let it soak in according to directions. Then use an old rag or sponge to wipe it away. In most instances scrubbing shouldn’t even be necessary.

After a thorough cleaning with Spray Nine, surfaces do seem to have solid protection. Some people even report surfaces clear from mildew for up to a year afterwards. That’s a pretty good result.

The smell of this stuff isn’t necessarily all that great. But it’s not as harsh as some bleaches, either. So just be aware that, as always, you’ll want ventilation when you’re using it.

One thing you might want to look into is the label here. Many other uses have said that this marine formula and the regular Spray 9 formula are the same thing. If that’s the case, you may save a few bucks just buying the regular stuff. This is really a great overall product, though. If you can’t find the marine version, Spray 9’s normal mildew remover should get the job done for you.

This one may not look like much, but 3M has never been about flashy labels. The product, however, is hardcore. This is a bleach based formula and it definitely is bleach heavy. There’s more inside though, including something 3M lists on the label as a trade secret. Take from that what you will. We don’t know what it is either, but we can tell you it works. 3M’s mildew stain remover will cut that mildew down to size.

One thing you need to be aware of is that this stuff smells intense. While it is a mixture of chemicals, bleach is all you’re going to smell here. In an enclosed space it gets overwhelming fast. Not only do we recommend good ventilation, this might be best with a mask. It can irritate your eyes, noses and throat pretty quickly otherwise.

The other thing to look out for is how this works in the sun. Many of these cleans are affected poorly by a hot, sunny day. This one is no different. We’d recommend waiting for a cloudy day or finding some shade, if possible.

In terms of use, this one is a breeze as well. Spray on and wipe away with a rag. If you have a serious stain, you’ll want to let it soak. Give it up to ten minutes and then try scrubbing with a soft brush. Wipe and rinse and see how it looks.

This is best for things like vinyl and fiberglass. You want to avoid this on cloth and carpet. Wood and painted surfaces won’t work well with this product either, so keep that in mind. They also recommend avoiding exposure to metal and porcelain. So keep that in mind while you work, as sometimes cleaners can run from one surface to another.

CLR is a popular household cleaner. The name stands for Calcium, Lime and Rust. It’s great for cleaning sinks, coffee pots, all that kind of thing. But their mold and mildew cleaner is an excellent choice for boats. Normally we wouldn’t recommend too many non-marine specific cleaners for this job. But CLR’s formulation is both safe and effective. It is a bleach free cleaner which means you won’t have that harsh bleach smell here. In fact, CLR is part of the EPA’s Safer Choice Program. That shows consumers products that use chemicals that are not as harsh and dangerous.

CLR is incredibly diverse and versatile. You can use this on almost any surface. They recommend testing it discreetly before trying fiberglass, however. That’s why this is not a marine-specific cleaner. That said, many people have had a lot of success using this on their boats. We can’t say for sure it’s 100% safe, however. If the company said you should test it out first, we have to take their word for it. But for us, and others, it seems to work great on fiberglass. Just be aware and follow precautions first, just in case. They don’t say not to use it on fiberglass, just to try it first.

Fiberglass aside, you can use CLR on wood, painted surfaces, fabric, glass and more. They caution against stainless steel. And they also recommend you use gloves and a mask when cleaning. Also keep the area ventilated. But that’s our advice for every cleaner as well. It’s a good habit to get into at any time.

In terms of application, spray CLR on the stained area.Give it about 10 minutes to do its magic. Then wipe it clean with a dry rag. There is also a foaming formulation you can try if you want. This one may be better for tougher stains. The foam sticks in place so it is able to saturate the stain better. It depends on your preferences, really. The formulation seems to be mostly the same.

If you hate the smell of bleach in other cleaners, CLR is a great choice. You can have some peace of mind knowing it is environmentally friendlier than some. It may cost a little more but that really pays off in the long run.

Boater’s Edge mildew stain remover is a solid choice. Don’t let the label fake you out, though. It says it’s designed for upholstery. That may make you think it’s limited in function, but that’s not the case. For whatever reason, the company chose to only highlight the fact it’s good for upholstery. That means your vinyl and stitching can handle the cleaning. But it’s also very effective on many other surfaces.

You can safely clean fiberglass, tile, plastic, and more. Amazon says it’s safe to use on wood but that is not actually correct. You could use it on wood or painted surfaces, sure. But only if you plan to paint them afterward. That’s something worth keeping in mind.

This is another buffered bleach formulation. That means it is bleach based and it could damage fabric. However, it’s designed to not harm things like thread and stitching. It should still be used with the same caution you’d employ with other bleach cleaners. Keep those vents open and get plenty of air. Consider gloves or even a mask if in an enclosed space.

Like other formulas, this one advertises a simple clean up. Spray, let it eat away the stain, then spray clean. But you may notice that one application is not enough. A bad mildew stain will likely withstand a single treatment. That means you may need to go in for round two. In that case, treat the spot again. Then use a dry, soft-bristle brush. Scrub the spot lightly and see if you can get the stain to come clean. Rinse again and see how it looks.

For most stains it should power through them pretty easily. Just be aware that you may have to put in a little extra time with this one.

Star Brite is back for its second appearance. Why Star Brite again? This is a slightly different product. It’s good enough at what it does that we thought it was worth listing. This is their Ultimate Mildew Stain Remover gel formula.

Like others, this is a buffered formula. You can confidently use this on vinyl, fiberglass, plastic, even painted surfaces. The big selling point for this one is the consistency. It probably cleans as well as the original Star Brite formula we mentioned. But as a gel it can potentially be much more effective.

If you have serious mildew stains, this is a great choice. Or if you have them in awkward spots, like up on walls or even the ceiling. Because this is a gel, it holds fast. You can apply it literally anywhere. It won’t run and drip like most other cleaners. Because it holds its position it can soak in no matter where you need it. That may not be a big deal all the time, but it is sometimes. And when you need a cleaner for an awkward spot, you’ll be glad you have this handy.

Like the other Star Brite formula, application is easy. Spray it on and let it sit. If you have a serious spot to clean, you may need a brush for scrubbing. Get into those hard to reach spots as best you can. Then, when it’s all done, rinse away. It’s easy and pretty quick overall.

Take caution with this formula, however. The smell of this is pretty strong. And, since it’s gel, it sticks. If it gets on your clothes or your skin, it can cause some damage. So even more than the other products, be smart about using this one. You must have good ventilation before using this.

Concrobium is a good product for light mildew stains. It’s also good if bleach cleaners really bug you with their fumes. This is a non-bleach cleaner. They also advertise it as odorless and that’s basically true.

The formula here is sodium carbonate and TSP. Both of those are pretty common cleaners that are not as chemically harsh as bleach. TSP is not necessarily something you want on your skin, however. And it can be damaging to the environment in large amounts. But the amount in this cleaner is very low.

One thing to be aware of is how this works. You spray it on mildew and let it dry. If you scrub or rinse it away, it won’t work. What happens is, as it dries, those chemicals in it crystalize. They literally crush the mold as it happens. When fully dry, the crystals will shatter the mildew and you can wipe it all away. But you need to follow those directions!

If it isn’t allowed to dry fully, it won’t work. This includes if you use it in a place that’s just too humid or damp. Keep that in mind. But if it is allowed to work properly, it’s actually remarkably effective. And far less harmful than many other chemical cleaners.

One of the best things about this cleaner is the after effect. It will prevent mildew from regrowing fairly effectively.

Sick of awful chemical smells? Lemocide can take care of that for you. Aside from being effective at eliminating mold and mildew, it has a lemon scent that is much less harsh.

Lemocide is an industrial grade cleaner. You wouldn’t need to buy this for any small cleaning job. But if you have a lot of mildew to power through, consider it. If you just bought a new boat that needs a real solid overhaul and cleaning, this may be what you need. This stuff is used in schools and hospitals to kill mold, viruses and bacteria. It can stand up to most tough jobs with ease.

Definitely make sure you follow directions closely. You need to dilute this with water before use. It goes 64 parts water to one part cleaner. You don’t want to mess with this cleaner because it can be dangerous if used importly. Keep things well ventilated and use gloves.

This will kill mold and mildew pretty much on contact. Then you’ll need to rinse or wipe it away when done. When used as directed it’s highly effective. The formula is used in industrial settings including in agriculture. That means it’s safe to use if you have pets. Just make sure you follow directions for cleaning up. It’s still something you don’t want to breathe in or get on your skin too badly.

The company offers a 30-day money back guarantee on the cleaner as well. That’s not something you’ll see from most cleaners, so it’s a nice touch.

Earthworm is another product designed with safety in mind. It cleans by way of natural enzymes rather than harsh bleaches. It’s also free from fragrance, so if smells bother you maybe give this a try.

Shake the bottle before you use it. Unlike some, this one seems to need a good jolt to mix it properly. Spray the surface you’re cleaning and let it sit for about 5 to 10 minutes. You can use a soft brush to scrub it after that time. The enzymes can continue working even after that. If you have a tough stain, it may take a while to power through. A second application can be used if you have severe mildew stains. But one application should get the job done for you. Just rinse it off and start again if you need to, though.

The fact it’s environmentally friendly is a big selling point here. And the lack of odor is also nice. Still, make sure you use it in a well ventilated area. That’s just a good habit to get into. Because it’s not a harsh chemical it’s safe to use on a lot of surfaces. You can even clean mildew off of carpets with this.

Don’t expect this to be as powerful as some bleach cleaners. You’re likely going to need to give the surface a good scrub after using it. But it should be good for some lighter mildew stains.

Nautical Ease has a biodegradable formula. That’s for if you’re worried about the environment, and you should be. You should take every step to avoid any cleaner getting in the water. But if it does leak out a little, it’s best to be environmentally friendly.

This brand is a little pricier than some. But it can offer results to match the price. It’s a solid choice for dirt, grease and mildew as well. The formula is safe for many surfaces including vinyl and fiberglass. It’s also safe for aluminum and stainless steel. Be aware that this is not recommended for anything with a porous surface, however,

When using on mildew, you’ll want to let it sit for a short while and then scrub. It may take a couple of applications. We also recommend wearing gloves. Non-toxic though it may be, it can cause a reaction. You’re better off being cautious, just in case.

It can take a bit of elbow grease to get this to work. You may need to scrub a bit harder, but the results do look pretty good. And it handles vinyl really well. Just be careful with older materials. If you have stiff, old vinyl this may make it look a little off when you’re done.

For new or light mildew, this is a great choice. Often all you’ll need is to let it rest a minute or two, then wipe away. Another thing to watch out for is sunlight. If you’re cleaning on a hot, sunny day it may cause this stuff to work faster and dry faster. You’ll have to match that speed in the sun, if you’re not careful.

The final clean dries to a nice looking shine. It will also protect against the return of dirt and mildew as well. Overall, this is a solid choice for a non-toxic and biodegradable cleaner.