What Are The Black Dots on my Window Sill?

What are the black dots on my window sill? Well, these dots can simply be dirt that has accumulated over time. However, in some instances, the dots could be insect droppings.

Insects are highly likely to poop on window sills since windows normally serve as convenient gateways to move in and out of houses.

How Can I Identify the Black Insect Droppings?

Identifying the type of pest dropping is very important for the elimination of these insects in case of a possible infestation. It also prepares you mentally regarding what type of insect is around your home.

Below is an overview of common insects that are likely to poop on window sills and how you can identify the droppings:

  • Cockroach droppings: they are usually small pepper black specks or flecks. Generally, they usually look like coffee granular and have groves with a cylindrical shape.
  • Carpenter ants usually have black droppings that appear like sawdust.
  • Termite droppings: they are usually big enough and resemble poppy seeds. If you observe them very carefully, you will find that these rounded pellets have some sides. Even though the droppings are mostly black, you might find that some of them are multi-colored. This is because what the termites eat also plays a crucial role in determining the color of their poop.
  • Fly droppings: they usually have a dark deep color and are really hard and dry to touch.

It is important that you find a way to get rid of such droppings. For starters, some of them are highly infectious and can lead to the development of bacterial infections. Secondly, some of these droppings can trigger allergic infections such as asthma.

Why are the black dots concentrated on my window sill and not anywhere else?

The window sill is usually the perfect spot for insect droplets to collect. This is an entry point and they usually land here before they can get in the building.

Window sills also contain wood materials that most insects love to feed on or to make nests inside.

Are they something I should be worried about?

Generally, you need to start being keen. This is because insect droplets can indicate a possible infestation or basically nothing to worry about.

One of the most common issues that people first notice before they deal with pest infestation is a collection of pest droppings in certain areas, especially the window sills.

These are places where they are likely to crawl and nest in as they move in or out of your house. If this is the case, then you have all reasons to worry about the pest problem. It should be noted that the more the droppings, the higher likelihood that the infestation is huge.

However, if the droppings are quite small, then chances are that maybe these are just random insects and, therefore, you should never worry about anything. The best thing at this point is for you to be watchful because anything can happen.

What rooms Am I more likely to find insect droppings in?

Example of fly droppings on window sill

This usually depends on the type of insect. You can find insect droppings anywhere but there are some rooms that are associated with specific insects. For instance, you are most likely to find bedbug droppings in the bedroom area, close to the bedframe, and in beddings.

Roaches usually poop anywhere. However, much of their droppings are usually near their feeding or nesting areas. So, you are more likely to find an accumulation of their poop in the kitchen close to the stove where there are likely food droppings. You can also find roach droppings on the shelves as well as the pantry.

Flies usually love dirty and damp places. So, their droppings are likely to be close to the dirt bin, sink, and bathroom among other places. Lastly, ants usually leave their excrement on kitchen walls or any other room where they are likely to nest.

What pest traps could I set up near my windows that would reduce the droppings?

Window sills are not huge spaces so you need to make sure that you install a small pest trap that can fit in such an area. The best types of traps are usually sticky ones. For instance, you can install small objects that are covered with sticky materials.

Generally, clear panels are usually the most effective since the insects can’t tell them apart from your window. The sticky traps need to have an attractive chemical element that the insects will find irresistible. For instance, Tangle-trap is a good solution and you simply need to scoop the insects off once they have accumulated.

If the insects have wings, then you should consider setting flying traps. Water pan traps are also good, especially on window sills. You can place a poisonous solution just to be sure that you can effectively eliminate the insects.

How Can I Clean the Insect Droppings?

Cleaning of insect droppings is something that you can do in a couple of minutes. Just make sure that you have the right cleaning materials. This may include:

  • Your usual household detergent
  • Cleaning rag
  • Vinegar
  • Cleaning brush
  • Warm water

Use the bush to remove the droppings

This is the first and most essential part. You need to first collect and remove the droppings so that you can effectively clean the area.

Remember that some of these droppings may have accumulated over time without your knowledge.

So, make sure that you use a brush with strong bristles to sweep and collect everything.

Apply the Cleaning the cleaning detergent

Whether you are wearing a glove or not, it’s important that you eliminate any chances of bacterial infestation by applying the cleaning detergent. Let it soak in for a couple of minutes to ensure that every little microorganism is eliminated.

Wet the surface

Soak the cleaning rug in water and then wet the window sill. Allow it to sit for a while before you can go ahead and rinse everything off. At this point, some of these droppings may have formed stains on your window sill.

Well, do not use bleach at this since they may lead to discoloration? Additionally, do not be tempted to scrub harder, especially if your window has some paintwork.

It would be nice to wet the surface again and wait for a couple of minutes as the water soaks in. alternatively, you can get a stronger cleaning agent that can effectively remove stubborn stains.

Thereafter, you can wipe off the deep marks and wipe the surface dry. The idea of using a vinegar solution after cleaning is just to ensure that every little microorganism that could have probably remained point. Also, vinegar is a good alternative solution bleach since it has moderate effects.

Will regular household cleaning products work?

Regular household detergents are the best for cleaning such wastes. They are readily available and have strong anti-bacterial properties. Besides that, they are also gentle on the hands. So, this is definitely the best alternative for you to use.

How to Prevent These Droppings from Appearing Again

Generally, it all depends on the management technique that you apply. The best way to prevent insect poop from reappearing from your window sill is to prevent the chances of possible infestations in the future. So, here is how you can go about it:

  • Ensure that you have a fully functioning window that doesn’t have cracks. It should be noted that when a window is faulty, it tends to attract unwanted guests like insects since they can find easy accessibility to your home.
  • Ensure that you have strong window draping in case you decide to open the windows. This acts as an effective barrier in ensuring that you limit the chances of attracting insects indoors. However, you can still enjoy the fresh air and sunlight at the same time.
  • Ensure that you effectively install a window caulk to limit air leaks that could lead to the development of insect access joints, cracks, and gaps.
  • Frequently clean the window and the sill to eliminate the accumulation of dust and dirt that may attract the insects.

Reduce the number of items that you place on the window sills. This can act as an effective breeding ground or nesting area for these insects.


Overall, the black dots on your window could just be dirt bought in by the wind. But if you see an accumulation on the window sill, it could mean that there are certain insects nearby.

Well, they could just be probably passing. Meanwhile, this could also be a sign of infestation.

Apart from the window sill, you are also likely to find insect droppings in different rooms. This may include the kitchen shelves as in the case of roaches or in washrooms in case you are dealing with termites.

However, make sure that you effectively clean the droppings. They are not only unsightly but could also pose serious health risks.

Once you have eliminated the poop collect, monitor your window sill from time to time.

This way, you will effectively thwart any chances of pest infestation in time before the effects are widespread.

If you want to learn more about various insects, then checkout our site categories, we have a bunch of articles there that are totally worth reading:



Pest Category




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All the best


Steve Foster

Mad about bugs and wanting to publish as many articles as I can to help educate people about these amazing beautiful creatures! For more info check out my about page https://schoolofbugs.com/about-steve-foster/

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