How to Remove Water Spots from Cars: A Step by Step Guide to DIY

Have you noticed stubborn water spots on your car? Wondering what these things are and how on earth you can remove them from your vehicle?

If you’ve never dealt with these before, they can look easy to take care of at first, but can prove to be rather tough to remove.

When they appear on your windows, windshield, or on your car’s body, these stains aren’t only unaesthetic, but they’re also likely to damage your vehicle’s paint as well.

Now, now – I know what you might be thinking: “How on earth can water be harmful to my car?”. Well, they’re never just water.

Depending on where you live, they can contain different minerals, which may be more or less corrosive. Luckily, you’ll have several options to choose from when it comes to removing them.

Very dirty black car in desperate need for cleaning


Let’s first discuss what these water spots are, how and where they’re formed, and why it’s super important that you remove them on a regular basis and don’t learn to live with them.

We’ll also outline, step by step, the best ways and different methods you can follow to remove water spots from your car.

Finally, we’ll dive into how you can save yourself on all of that time and effort by preventing water spots from making an appearance on your vehicle in the first place.

By the end of this article, removing these stains should become an easy routine for you to follow on a regular basis – one that’s unlikely to cause any damage to your vehicle.

What Are Water Spots?

These are the tiny white circles found all around your vehicle after the droplets have evaporated and dried. They’re often composed of minerals contained in the earth that make their way into water.

Depending on the source, it can also contain harsh chemicals or even acid.

Who Do Water Spots Concern?

Although they can be more apparent on dark-colored cars, any car owner should be concerned with water stains, and should know all about how to deal with them if they ever needed to.

Vehicles often represent a large investment for many of us, and most of us do our best to keep our rides shiny and in their best shape. It’s not just for those of you who take your cars to shows to worry about this!

Where and When Do Water Spots Form?

These pots can form all over a vehicle, and there’s not just one specific area they tend to be focused on.

For example, they can be found on the windows, windshield, but also on the car paint and clear coat. As mentioned, they’re more easily noticeable on dark-colored cars.

They’re a year-round issue, too. In summer, they tend to be more aggressive due to the sun and heat intensity. Come winter time, constant weather and rainfalls makes it more difficult to keep your vehicle dry.

How and Why do Water Spots Form?

Water stains form when drops of water are left undried on your vehicle. The liquid evaporates, and the minerals and other constituents attach to the clear coat of the vehicle.

This happens more often than one may think, and for a variety of different reasons as well.


Are you under the impression that rainwater is pure of minerals and contamination? Unfortunately, this isn’t the case. Rainwater contains a variety of minerals, such as calcium, magnesium, potassium, chloride, and many others.

Before rainwater reaches us, each droplet goes through our atmosphere, catching pollution and other contaminants on its way. Dirt, dust, and airborne elements are also caught within the drop.

If you’ve parked under a tree, rainwater may have picked up tree sap components before reaching the surface of your vehicle.

Water Puddles

In winter, rainfall easily accumulates on the road, forming puddles of water. Driving through puddles, or getting splashes from cars driving through them, will get your vehicle covered with stains.

These usually affect the lower to mid-sections of your vehicle.

Puddles don’t only contain mud and debris from the ground – they can also be composed of chemicals found in concrete, petrol, and other pollutants from passing cars.

In winter, you’ll also find a large amount of salt, which is extremely corrosive.

Car Wash

If you’re not properly drying your vehicle after an automatic or manual car wash, water spots will also form.

Regular water used for a car wash might not be as toxic as puddles droplets. It does, however, still contain chemicals and trace of minerals, which can leave marks behind.

The quality of the water greatly depends on where you live, and may contain different types of minerals or chemicals.


Watch out for hidden sprinklers, as you might not see them as you’re parking.

As they turn on, they’ll splash the same type of droplets as you would get while washing your vehicle.

Different Types of Water Spots

Mostly, three categories of can be found on vehicles. They’re often determined by the level of damage they’ve created.

Let’s have a detailed look at each of these three types in the following sections:

Hard Water Stains

Tap water often ranges from 140 to 400 ppm (also called total dissolved solids or TDS) depending on the city you live in.

Although there are several degrees of hardness, it’s considered ‘hard’ when the levels exceed 120 ppm. It’s then very likely that you’re rinsing your vehicle with hard water.

Hard water is pulled from groundwater, and is the type of water most of us use to wash our cars.

It travels through the earth, absorbing minerals (mostly calcium and magnesium), dirt, pesticides, and potential chemicals on its way.

Bonded Mineral Contamination

These types of stains are caused either by high mineral concentrations or repetitive, continual exposure. Over time, these minerals form hard bonds, attaching to the car paint.

These stains are difficult to remove and often leave a dull mark, or can even chip your car’s paint.


When the water contains a corrosive compound, it can go through the clear coat and attack the car paint directly, creating a small crater. These types can also form on glass.

Etching is considered to be the worst type of stain, and happens particularly when the vehicle is left to dry under direct sunlight. It often occurs when a high amount of chlorine is present in the water.

When a volcano is located nearby, etching can be created by acid rain. This is also called sulfuric erosion.

Once the crater has formed, the droplets tend to find their way back to the same spots, creating deeper marks.

Etchings can be mild to severe, and are the most difficult stains to remove. Often times, they can even require wet sanding to be corrected.

Why Should I Remove Water Spots From My Car?

You might only dry off the droplets after a car wash for aesthetic reasons.

White marks remove the shiny and clean appearance that most vehicle owners look for, and they become even more apparent on dark-colored cars.

Knowledgeable and experienced car owners also understand that the longer they wait to remove these water spots, the more difficult it will be to get rid of them.

After some time, these stains can leave permanent marks that are both time consuming and costly to remove.

The accumulation of minerals on the clear coat makes car shampoo less efficient.

On windows, droplets can also create scratches.

Items and Accessories Needed to Remove Water Spots

Here are the main items you might want to consider keeping at hand for whenever you need to perform this task.

In another section further down, we’ll talk more about how you can use these items and accessories.

  • Microfiber cloth.
  • Cleaning mitt.
  • Water hose.
  • Two buckets. Any bucket would work, but the ones featuring wheels are easier to use and move around your vehicle.
  • Food-grade white vinegar.
  • Distilled water.
  • Sponge.
  • Protective wax.
  • Clay bar kit and lubricant.
  • Polisher.
  • Grit sandpaper.

How to Remove Water Spots from Cars

There are several different ways you could go about doing this and several methods to follow.

One thing’s for sure, though – you should always try the least aggressive cleaning method first.

Car Wash

To remove fresh, recently acquired spots, a simple car wash might be enough to get the job done.

If stains remain, a full car wash is a prerequisite for all other cleaning methods further described.

  1. Place your vehicle indoors or away from direct sunlight.
  2. In a bucket, mix a double dose of your favorite cleaning solution with warm water.
  3. Use a second bucket with only warm water to rinse your mitt.
  4. Using a hose, spray all over your vehicle avoiding the window edges (in which case water could get in).
  5. Using a clean mitt and your warm soapy water, clean your vehicle throughout, starting with the wheels.
  6. After cleaning each section, rinse with the hose. Ensure that the entire vehicle stays wet at all times to prevent the drops from evaporating.
  7. Dry the entire vehicle with a clean microfiber cloth.

On a rainy day, try washing (and drying) your vehicle soon after the rain stops, either the same day or the next morning.

White Vinegar

For stubborn spots, the acidic nature of white vinegar can be of great help.

Minerals, such as calcium, have a high pH factor. Low pH solutions, such as vinegar, are able to dissolve such minerals.

  1. Wash your vehicle thoroughly using the previous method.
  2. Mix equal amounts of vinegar and distilled water in a bucket. It’s important to use distilled water to avoid altering the pH of the vinegar.
  3. Using a clean sponge, use the mixture and apply to a small area.
  4. Leave the liquid work its magic for a minute or two before rinsing gently.
  5. Dry the area before starting on the next stain or area of your vehicle.
  6. Vinegar removes any protective wax layer. Reapply your regular protective wax across the entire surface of the vehicle.

Vinegar will work best on relatively fresh and new spots.

Clay Bar

Clay is a popular and efficient remedy to remove water stains from cars. Calcium and other minerals tend to adhere to clay without damaging the paint.

  1. Proceed with a complete wash as described earlier.
  2. Soak the clay bar in warm water.
  3. Spray clay lubricant over the area.
  4. Using the clay bar, attack the spots from every angle to remove the minerals. You might need to repeat this process a few times to remove the most stubborn ones.
  5. Dry the area using a microfiber cloth.
  6. Apply a layer of protective wax.


If these methods don’t prove to be successful, then you’re most probably dealing with more serious stains or etching. In this case, you’ll need to level or polish the clearcoat (or paint) throughout to remove the spot.

You can use a round polisher device to level the stain on your own. With that being said, we would only recommend proceeding with this task at home if this is a project you’ve successfully handled before. If not, it’s probably best to have a car detailer do it for you.

  1. Wash and dry your vehicle.
  2. Polish the area using light pressure.
  3. Using a microfiber cloth, wipe the area.
  4. Apply a layer of protective wax.

Wet Sanding

When polishing fails, it’s often best to leave a professional handle the reparations.

The wet sanding technique uses very abrasive sandpaper to remove the stains. If you feel like this is a task you can handle, here is the step-by-step procedure to follow:

  1. Wash and dry your vehicle throughout.
  2. Fill a bucket with warm water and regular soap.
  3. Soak half of the sandpaper’s length (1200-1500 grit) into the soapy solution for five minutes.
  4. Wrap the dry portion of the sandpaper around a pad or squeegee.
  5. Start sanding, applying light pressure and making small circular movements.
  6. When the sandpaper gets dry, add water.
  7. Repeat the process with a 2000-3000 grit sandpaper. This will remove any potential scratches made with the previous sandpaper.
  8. Rinse and dry the area properly using a microfiber cloth.
  9. Polish the area using a polisher device.
  10.  Apply a layer of protective wax.

How to Remove Water Spots On Glass

The above methods can be used on your windows or windshield as well. Glass is sturdier than your vehicle clear coat, so more abrasive cleaning methods can be used.

Aggressive household cleaning products can be used as well, ones such as Bonami cleaner or regular glass cleaners. A steel wool pad can help penetrate deeper into the stain.

If the spot remains, polishing can also be used on glass, but with light to medium pressure only.

How to Prevent Water Spots From Forming Again

Just like almost every other problem that your car could ever experience, prevention is best.

It’s much easier to prevent them from forming altogether, than it is to remove hard water stains or even etching.

Keep the following tips in mind to make sure this problem is kept at bay.

Avoid Washing Under Direct Sun

Most car owners tend to wash their vehicle outdoors, under the sun.

This is the most convenient option for many, me included, but is also sometimes the only place available to wash a vehicle.

If you don’t have an indoor space such as a garage or shaded yard to work in, we recommend washing your vehicle in the early mornings or late evenings to avoid the excruciating sun and hot hours of the day.

Apply a Wax Coat Regularly

A wax layer applied on top of your clear coat might prevent regular spots from forming.

The stubborn stains will stick to the wax coat and not to the clear coat directly. This makes them much easier and safer to remove.

Stay Away From Sprinklers

This might be the easiest prevention tip, and only requires a little attention.

Although sprinklers can sometimes be hard to spot, have a quick look around before parking to make sure they’re not around. This can remove a lot of frustration and save you some precious time!

Keep a Cleaning Spray at Hand

Even the most experienced taskmasters can’t control every situation they’re ever faced with.

You’ll most likely be stuck in a rainstorm, drive through water puddles, or find your car parked beside a hidden sprinkler at one point in time.

Keeping a cleaning spray and microfiber cloth at hand in your car at the ready for whenever you need it will keep you prepared for any unforeseen circumstances that might arise.

Know What’s in Your Water

A little research can go a long way – and this is very true when it comes to the water you use to wash your vehicle.

You might not need to know all the components and chemical constituents of your city water, but being aware of specific corrosive or acidic compounds it might contain can help you keep your car in pristine condition.

If you’re having difficulty finding all that information, your town water can be measured using a TDS Meter. This electronic device displays the amount of ppm present in the water.

Invest in a Car Cover

When not in use, it’s easy to forget about your ride – and rarely does that ever result in good things …

Waterproof car covers can be used on a daily basis. All you’ll have to do is place the cover on at the end of the day, so that your car spends the night dry and protected from all the nasty elements that could make their way on its exterior.

When parked outside for a long period of time, car covers provide an extra layer of protection.

De-Ionizing Filter Systems

Did you find out that your city water contains a high level of minerals or acidic compounds? You’re not lost, and many of us are in the same boat.

This is where filter systems can come in very handy. Some filters, such as CR Spotless System, are able to de-ionize the water to remove all minerals contained in it.

The device removes any impurities and can be used safely without any risk of leaving water spots behind.

They often come at a high price point, though, which means that they might not be suitable for all budgets.

Regular Filter Systems

Filter systems can be used to remove harmful components before they get to your vehicle.

They aren’t as efficient as de-ionized filter systems, but are more affordable. So, if you happen to be on a tight budget and can’t spend all that much, regular filter systems can be the perfect solution for you.

These filters are easy to set up, and need to be replaced every couple of months.

Try Rinseless Washing

If purchasing a filter system isn’t an option for you at this time, for whatever reason that may be, then rinseless washing will limit the amount of water present on your vehicle.

It consists of cleaning a small portion of your car with soap and water, and drying it immediately.

For example, the Optimum No Rinse cleaning solution is a very popular choice for this type of car wash.


Indeed, a car can be high maintenance. Not only do you need to stay on top of everything to make sure it’s functioning properly, but you also have to invest time, energy and money into making sure it looks its best, too.

We hope this article makes you feel a bit more confident about getting rid of water spots on your car! As you’ve seen, a solution exists for all types of stains, and even the toughest ones can be removed.

If you aren’t all that comfortable with working on your vehicle yourself to remove water spots, or you’re afraid that you might do more damage than good, then don’t be afraid to contact a professional who will be able to guide you in the process.

Sure, it might cost you some money, but it’s saving you time and you’re getting the help of someone who knows exactly what they’re doing.

When looking to save time fighting water spots on your car, the best method is always, always, always prevention. Do whatever it is you need to do to make sure they don’t make it on your vehicle, and you’ll be a very happy driver!

From childhood go karting and motocross, to collecting and obsessing over scalextric, matchbox and radio controlled cars, I've always had an obsession with cars. Learning through manuals, books, trial and error, and more knowledgeable family members, I've also enjoyed tinkering with the mechanics and electronics of any vehicles I've owned. Now, over 3 decades later, I've started this site as a place for me to share my knowledge, to teach others how to care for and maintain their vehicles themselves, at home, so they can get the most of their vehicles and save a pretty penny compared to always seeking out professional help.

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