Boric acid powder for roaches

Keeping your home hygienic is crucial for your family’s health. A pest problem results in an unhealthy home environment, especially for your children.

An effective method to kill those roaches is to use boric acid powder. Read on to find out more about this magic powder and how you can use it to get rid of roaches for good.

In this article, we’re going to review the following boric acid products:

What is Boric Acid?

Boric acid is an inorganic, odorless, non-volatile white powder than contains boron, a natural element. Boron is mined from mineral deposits and is then combined with water to form boric acid. You can easily find this powder at your local grocery store.

You can either buy it in its generic form or as roach killer that’s packaged in plastic bottles. Most of the time, boric acid powders don’t need to be mixed or diluted before use, but some of them do.

In addition to killing roaches, boric acid is used in some acne-treating products and treating ear infections.

Does Boric Acid Kill Roaches?

Boric acid comes in powder or dust forms. It’s electrostatically charged. This makes it cling to a cockroach’s body when it walks through the powder. The roaches will then go back to their nesting areas, infecting other roaches with the powder on their bodies.

When the insect grooms itself, it ingests this dust. The dust attacks the nervous system of the cockroach, causing damage to its outer body, in addition to dehydration. The roaches will behave in an abnormal manner like coming out during the daytime in exposed areas.

Moreover, since roaches are cannibalistic, they feed on their dead, further spreading the infection among themselves.

Boric acid is guaranteed to kill all types and ages of roaches. It’s one of the most effective ways of dealing with them.

After a roach is covered with boric acid powder, it’d take around 72 hours for it to die. Nymphs and juveniles usually take less time to die, a maximum of two days.

How to Use Boric Acid to Kill Cockroaches?

Boric acid isn’t that toxic to humans but is highly toxic for roaches. Before applying the powder, you need to make sure that you’re applying it in the right places.

Cockroaches usually hide in kitchens and bathrooms. You may find them in other areas of your house but that’s less likely. To make sure you’re applying the powder the right way, carefully follow these steps.

  1. Empty your kitchen cabinet and the region under the sink.
  2. Clean everything in the kitchen with detergent and some water, including the sink, cabinets, oven, drawers, and countertops. You can use some DIY kitchen cleaners too.
  3. Be careful not to let any of the boric acid powder to get in contact with your kitchen countertops or any surfaces used for food preparation. Wipe these surfaces thoroughly with a damp cloth to make sure that they are free of contamination.
  4. Clean the area around the refrigerator. Remove and clean the pan that collects the defrost water under the refrigerator.
  5. Fill any holes or crevices in the walls with a foam filler. This prevents roaches from taking these holes as their home.
  6. Spread the boric acid throughout the kitchen cabinets, drawers, countertops, and sink. Make sure you apply it under the sink, oven, refrigerator, and dishwasher. Be careful not to inhale the powder when applying it.
  7. After you’re done with the kitchen, clean the bathroom and apply the boric acid in areas like under the toilet and the sink.
  8. It’s advisable to apply the boric acid at night and leave it until morning. That’s when roaches come out. If your house is filled with lots of roaches, a heavy application may be required and it’d be better if you stay out of the house for two to three days.
  9. The next morning, clean any residual boric acid and wipe the areas where the powder was applied using a wet rag.

Besides using boric acid powder to kill roaches, it can be a good idea to use another cockroach control product. A highly effective combination would be to use containerized cockroach bait in addition to the boric acid powder.

Mistakes Made With Using Boric Acid to Kill Roaches

Avoiding these common mistakes when applying boric acid will give you a much better result.

Too Much Boric Acid

The most common mistake many people make when using boric acid is applying too much of it. When a roach walks into a pile of boric acid, it’ll just walk around it instead of making an effort in climbing it.

A thin, nearly invisible layer of boric acid powder would be more than enough. You may need to use a bulb duster to achieve the required layer thickness.

Applying the Powder in the Wrong Places

Before applying the powder, you need to make sure that you’re applying it in the right places.

Applying the powder in areas away from where they’re living is just as ineffective as not applying any. Roaches usually hide in kitchens and bathrooms, so spread the powder in these high traffic areas for better results.

You may find them in other areas of your house but that’s less likely.

Boric Acid Products to Kill Roaches

It may seem like all boric acid products are the same, but that’s untrue. Some products are more effective in killing cockroaches than others. Furthermore, not all of them last for the same amount of time.

To help you make the right choice, we’ve reviewed some of the best boric acid products to kill roaches.

Zap-A-Roach Boric Acid

This roach killer boric acid is designed to eliminate some of the most stubborn pests to fight. It kills roaches, water bugs, ants, fleas, and silverfish. You get a double pack, each weighing 1 lb.

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Spread Zap-A-Roach throughout your home in the roaches favorite places, and they’ll be gone in no more than three days.

You also won’t have to worry about ruining your floor, because this powder is non-staining. It’s odorless too. Your guests won’t even notice you’re dealing with a pest problem.

To use this powder, shake it well and twist the cap until you hear a click. Hold the bottle at a 45° angle, then let the powder flow by squeezing the bottle. Furthermore, you can use a spoon to put the powder in the places that can be hard to reach.


  • Odorless and non-staining
  • Nearly invisible


  • Doesn’t come with a duster

Harris Boric Acid Powder

The Harris Boric Acid Roach Killer is guaranteed to be effective for weeks, taking only 72 hours to kill the roaches after application. It comes with a special lure that’s used to attract the roaches to the powder and trick them into feeding on it to their death. Moreover, the cockroaches carry the boric acid to their nests, killing the other roaches there.

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The straw is designed like a tube that’ll enable you to put the roach killing powder in the deepest holes and cracks.

This powder is registered with the Environmental Protection Agency (EPA) as safe for use (pdf) in homes with people and pets.

It’s available in two purchasing options, 16oz and 32oz. The 32 oz bottle comes with a duster which can be handy. The duster allows you to apply just the right amount of powder.


  • The powder can be used to kill other pests, like ants, waterbugs, and silverfish
  • Can be easily applied in areas that are difficult to reach thanks to the straw
  • The powder stays effective for a long time, making sure no more roaches will infest your house
  • 16 oz and 32 oz bottles available
  • Comes with a duster


  • Not exactly made to be used outdoors

Duda Energy Boric Acid

The H3BO3 granular is an industrial-grade boric acid with 99.9% purity. It’s also very fine, like salt crystals.

Mix it with sugar at 5% or less of the amount of boric acid. After that, add some water to the boric acid-sugar mixture and you’ve got yourself a lethal roach killing paste. All it takes is two to three days and you’ll wave goodbye to the roaches.

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There are some precautions for using this product. You must use it in well-ventilated places only. Moreover, it’s advised to wear a respirator during application. You also need to wash your hands and other exposed body parts after use.

Store the powder in a cool, dry, and well-ventilated area.


  • High purity, industrial-grade powder
  • Great value for money
  • In addition to killing roaches, you can use this powder to clean the toilet powder


  • Unlike other products that come ready to use, you need to prepare this boric acid by mixing it with sugar and water
  • The bag is a little hard to open
  • Doesn’t come with a duster. You have to purchase it separately
  • Can be used in well-ventilated places only and wear respirator during application.

A good alternative to these products would be to create your own DIY boric acid spray.

Safety Risks and Precautions

Although boric acid is generally unharmful to humans, getting it in your mouth, nose, or eyes can expose you to some level of toxicity, so use it with caution. It’s a good idea to use latex gloves to avoid irritating your skin. You should also wear a dust mask when you’re applying the powder to protect yourself from inhaling it.

Boric acid can also be toxic to pets, specifically cats and dogs, but it depends on the dosage. Overexposure may lead to hazardous problems. If you suspect that your pet was overexposed to boric acid powder, take it to a veterinarian immediately. I have reviewed pet safe roach killers before in case you want to use chemicals and have pests at home.

Generally speaking, people who have been exposed to a small dosage of boric acid powder showed nothing to be concerned about. Nevertheless, you still need to be careful when using the powder. Better safe than sorry.

Final Words

Our winner as the best boric acid powder to kill roaches is the Harris Boric Acid Roach and Silverfish Killer. The fact that it comes with a duster makes it a very attractive option to consider. Moreover, it comes with a straw, so you can apply the powder easily to those tight areas where roaches hide.

Boric acid will help you get rid of roaches for good. Just follow the necessary precautions and apply it in the correct places without applying too much of it.

Depending on how bad the pest is, getting rid of all the roaches may take some time. Be patient with the powder and you should see a decent long term result.