Black Stains on Hardwood Floor? (Here’s How To Remove Them)

Having dark water stains on your wooden floor makes the floor look aged and ugly. So how do you get rid of these black water stains?

You can remove black water stains by sanding the affected spot and using a solvent or solution like vinegar, baking soda, and hydrogen peroxide to wipe the wood.

Removing black water stains from wood is a trial and error process as you need to try out different methods till the dark water stain comes off. This is why removing black water stains is usually difficult.

You should stay away from strong acids like bleach as these substances can damage, corrode, and permanently discolor the wood.

This post explains more about removing black water stains from wood including several household products that can remove the stains. So, let’s dive in.

What Causes Black Spots on Wood Floors?

The main cause of back spots on wood floors is moisture. When the wooden floor is exposed to moisture for a long period, it will cause dark stains on the wooden floor. The reason the stain is black is that the water stain has penetrated the wood fibers.

Usually, black water stains start as white water stains. When the wood is exposed to moisture, the moisture will stay on the finish or top layer of the wood for a while where it will turn white.

At this stage, you are expected to wipe off the water stain. But, if you leave the water on the surface, it will gradually begin to soak into the wood where it will turn from a white spot to a dark stain inside the wood.

Here are other reasons for black water stains in the wood:

Chemical Spills

Another reason for black water stains on your wood floor is a chemical spill. If you accidentally pour chemicals on wood without wiping it off immediately, the chemical can damage the finish, soak into the wood, and cause dark stains. Strong chemicals can even cause the wood to rot. Fungicides, herbicides, chlorine, and the likes shouldn’t be poured on wood.

Drink Spills

Drink spills like red wine, soda, grapefruit wine, and the likes can cause black stains on wood, especially on unfinished or bare wood. This is because these drinks have colorants in their formula that can tint the wood floor and make it appear black.

Iron Oxide or Rust

Another common reason for black stains in wood is rust or iron oxide stains. This is usually common with wooden floors that have metal railings or fittings.

When the metal is exposed to constant moisture (water) and air (oxygen), it will begin to form frail iron oxide coatings on the metal. After a while, the rust will begin to fall on the wood and cause dark-brown stains on the floor.

So do black water stains eventually disappear? Let’s find out.

Do Black Water Stains Eventually Disappear?

Do Black Water Stains Eventually Disappear?

Black water stains don’t disappear on wood. This is because the water stain has penetrated the wood so it becomes impossible for the stain to fade out.

Also, the black water stain wasn’t caused by water. Since there are other ingredients and colorants in the stain, the black water stain will not disappear. Instead, the colorants will form a permanent discolored spot inside the wood fibers. The only way to remove black water stains in wood is to do so manually.

Usually, water stains on wood disappear after a while but this happens when the water stain was caused by just water. In this case, the wet stain will be water and a mix of wood tannins. When the water dries out, the tannins will blend into the wood and the wet stain disappears.

However, black water stains are caused by chemicals, rust, drink spills, and so on. All of these liquids have colorants and other ingredients dissolved in the water. When the water dries, these ingredients and colorants will not evaporate with the moisture. Instead, these colorants and chemicals will leave a permanent black spot on the wood that you’ll have to remove by yourself.

So if you notice black, dark-brown, or dark-blue wet spots in your wood, you have to remove them manually because they will not disappear. So how do you do this? Let’s find out.

How To Remove Old Black Water Stains From Wood Floor?

You should know that removing black water stains from the wooden floor is a tough task. This is because the wet stain would have penetrated the wood already.

So, to completely remove the wet stain, you need to get into the wood fibers which is very difficult. However, this post will show you how to do this easily in 7 steps. But first, we’ll need a few tools and supplies:

  • Clean rags
  • Mineral spirits
  • Sandpaper
  • Hardwood polish
  • Hydrogen peroxide
  • Paintbrushes
  • Baking soda or vinegar
  • A soft sponge
  • Hairdryer
  • Wood filler (optional)

Here is a 7-step guide to removing black water stains from wood:

1. Wipe and Clean The Affected Spot

Wipe and Clean The Affected Spot

The first step is to clean the stained spot on the wood. This is to get rid of filth, debris, and even moisture on the wooden floor. If you don’t do this, the filth will be ground into the wood while you try to remove the black water stain.

This will cause another severe case of black stains later. So ensure the wood floor is clean fast. To do this, use a clean rag to dab the stained spot. Then wipe the entire surface with a damp rag.

2. Use a Hairdryer to Suck The Moisture In The Wood Floor

Use a Hairdryer to Suck The Moisture In The Wood Floor

The next step is to suck out the moisture or water in the wood. To do this, use a hairdryer or heater. Set the hairdryers to medium heat and move it across the stained spot. The heat in the hairdryer will aid the evaporation of moisture from the wooden surface.

This way, you can be sure that there isn’t water in the wood. Ensure to move the hairdryer around the affected spot. If you stay on one spot, the wood can get burned or develop burn marks.

3. Soak The Affected Spot with Baking Soda Solution

Soak The Affected Spot with Baking Soda Solution

With the moisture out of the wood, we are ready to tackle the black stain. To do this, you need to mix 2 tablespoons of baking soda in warm water. Ensure to stir the solution to make a paste.

You don’t want the mixture to be light as it will easily soak into the wood too so make it thick. You can add cigarette ashes into the baking soda solution. The ashes will make the solution a bit more potent.

After, you can apply the baking soda paste over the affected spot and leave it overnight. Baking soda is an alkaline solution that will lift the black stain out of the wood. When it’s morning, use a clean rag to wipe the baking soda off of the wood.

If you are lucky, this step will remove the black water stain completely. If not, don’t sweat it. We still have a few steps to try out. Remember this is a trial and error task.

4. Wipe The Surface With Vinegar

Wipe The Surface With Vinegar

If the baking soda didn’t get all the black stain off, vinegar will. You can also use mineral spirits or hydrogen peroxide for this. Apply a bit of the solution on the stained spot and leave the solution for a few minutes.

After, use a soft sponge to massage the area. If you have an extra toothbrush, use it to scrub the area too. This will loosen and get the black stain out. If this step doesn’t work, then it means that the black stain has severely affected and soaked into that part of the wood. But don’t worry, here’s what you should do.

5. Sand The Affected Spot With Fine-Grit Sandpaper

Sand The Affected Spot With Fine-Grit Sandpaper

If the black stain didn’t come off completely with the baking soda and vinegar solution, then you need to sand it off.

The bad news is sanding the affected spot will take part of the wood. The good news is this will remove the black stain permanently. You are to sand the spot with fine-grit sandpaper until the black stain comes off. When the stain is off, wipe off the wood dust.

6. Apply Wood Filler (Optional)

Apply Wood Filler

It’s possible that sanding and using solvents on the wood floor would have caused gouges and dents in the wood. These spaces should be filled with a light coat of wood filler or joint compound. Ensure the wood filler dries smoothly and evenly into the wood. On average, this would take about an hour.

7. Polish The Wood With Hardwood Floor Wax or Polish

Polish The Wood With Hardwood Floor Wax or Polish

The final step is to polish the wood with hardwood floor wax or polish. These products are designed to set an amber-like tone to wood and they make wooden surfaces appear bright and glossy.

The biggest perk is that the hardwood floor wax or polish will protect your wooden floor from further wet stains as it is waterproof. After applying this, leave the wood floor to dry for about 3 days before normal usage and cleaning resumes. And, this is how you can remove black stains from wood floors.

Other Products You Can Use To Remove Black Stains

Next, let’s check out some common cleaning products and see if they can be used to remove black water stains from wood floors.


WD-40 will remove dark water stains in wood but it might leave stain deposits behind. This is because WD-40 is a blend of several solvents including fish oil.

So while the dark stain is removed, the WD-40 might leave deposits of its own formula in the wood as well. If you are to try this product, ensure you don’t let it sit on the wood for too long as this will cause it to be easily soaked in.


Mayonnaise helps to remove dark water stains from wood. The mayo acts as a water displacer causing the stains to come out of the wood.

However, you should know that may work best on fresh black water stains. If you are trying to remove an old black water stain on your wood floor, mayonnaise might not be enough.


Toothpaste can remove dark wet stains in wood. This is because toothpaste is an abrasive compound designed to remove dental scales or plaques.

However, just like you do while brushing your teeth, you’ll also need to use a scrubbing brush to scrub the affected spot. This is to massage the toothpaste into the wood where it will remove the dark stains.

The down part here is toothpaste might not remove the black stains all at once since it was designed to be gentle for your gum and teeth and not for wood. So you’ll need to do this repeatedly. To make the toothpaste stronger, you can also mix it with baking soda.

Pressing Iron

You can use a pressing iron to remove black water stains from the wood floor but this only works for wet black water stains.

Since the stain is still wet, a pressing iron will dry out the moisture and cause the stain to disappear. However, if the black water stain has dried out, then a pressing iron (heat) will not do much on the surface.

To use the pressing iron, place a cloth on the stained wood and put the pressing iron on the cloth. Ensure not to crack up the heat too high.


You can use salt to remove dark water stains from wood floors easily. This is because salt contains chlorine which is an acidic substance that dissolves color and kills germs. To use salt, mix a few tablespoons of salt in warm water and spray the mixture on the wood floor.

Hydrogen Peroxide

You can use hydrogen peroxide to remove black water stains from wood floors because hydrogen peroxide is an oxidizing substance. This means that the peroxide molecules in the solution will bleach the dark stain out of the wood.

How to Prevent Black Stains on Your Wood Floors?

Here are ways to prevent black water stains on your wood floor:

  1. Place waterproof mats or carpets on the floor
  2. Avoid spills and water stains on the wood floor
  3. Potty-train your kids and pets so they don’t pee on the floor
  4. Wipe and clean stains as soon as they occur
  5. Clean your wood floor frequently.
  6. Cover outdoor wood with drop sheets in the rainy season
  7. Apply a moisture-resistant and stainless finish on the floor. Lacquer is a good stain-resistant protective finish and it can be used on floors

Final Words

In summary, black water stains are nasty on wood floors but these stains will only occur if you allow them to. If there is a spill on your floor, ensure to wipe it off as soon as possible and don’t leave it to soak in the wood.

If the black stain has dried up, you can remove it by using a solvent or by sanding. Finally, ensure to cover your floors with waterproof carpets to prevent nasty spills.

Leave a Comment