Does bleach kill cockroaches? – true or false

Dave Campbell

When it comes to pest control, many people have considered using household bleach as a way to repel or kill various critters. But the big question is can bleach kill roaches?

The short answer is: no, bleach will not effectively kill cockroaches. Bleach is composed of chlorine and other chemicals that are designed to disinfect surfaces, but these ingredients are not effective at killing cockroaches. In fact, it may even make them stronger and more resistant to future treatments.

Cockroaches are insects of our nightmares, or at least for some of us. These hungry survivalists can be around the house very often – mostly due to the presence of a food source or several food sources like dirty dishes, crumbs, or pet food, these often lead to a roach problem. Other environmental factors which may attract cockroaches are excess moisture and the level of ease for them to make it into the home through cracks and crevices of your home, or the holes and pipes. The most common roach species that live amongst us are the American and the German cockroaches.

Of course, it is trivial that getting rid of these sources and sealing up potential entrances is a solution to this roach problems, however, that’s not really exactly practical especially if you have kids or like.. you know, don’t want to suffocate – you don’t want to always throw away the baby with the bathwater, but make sure to at least throw away your trash. In this post, we answer the question can bleach get rid of cockroaches or kill roach eggs too perhaps?

We will examine the effects of directly applying bleach to the cockroach’s skin, submerging the cockroach in bleach, or cleaning around the house with bleach so as it let the fumes fuse with the air. After answering these, you will quickly learn that using bleach as an insecticide is generally not a very good idea despite its effectiveness – alternatives are then proposed.

cockroach on the ground

The truth about treating a roach infestation with bleach

The answer to this question depends on the type of bleach you’re using, most household bleaches are composed mainly of Sodium hypochlorite (3-6% concentration in water). Another variant composed mostly of Chlorine Dioxide (in an aqueous solution) is what is known to kill roaches at about 3000 parts per million-hours. To make this gas one has to mix chlorine and pine-sol. Chlorine gas is highly toxic and can cause serious irritation to the lungs, eyes and skin, so be careful.

However, this gas is not safe to work with (even in aqueous “bleach” solution) since it’s known to cause throat and nose irritation when inhaled and is also generally a fire hazard. On the other hand, “normal bleach” (Sodium Hypochlorite) may work just as well and whenever the word “bleach” is used from hereon, this is the kind being referred to.

How does it work?

The smell of chlorine bleach is often a viable deterrent if you want to get rid of roaches. One way to make your house smell like bleach is to clean with it, often on surfaces and even floors (that’s if your floors aren’t carpets). Though this method is just going to keep them at bay, in this case – the presence of bleach, so like the pest they are, an old adage tells us that once the smell’s away, the cockroach will play and I bet not many people really want their homes constantly smelling like bleach. If you are going to try this method, don’t mix bleach with anything else apart from water.

So this method won’t repel roaches for long. But for some, this may be just what they need, a temporary solution but a bleach smell isn’t that pleasant to keep around. There are other products emitting a variety of more pleasant fragrances which are of use in dealing with a cockroach problem.

What smells keep roaches away?

Essentially oils often give out pleasant smells useful for relaxation – these smells can get really strong and a cockroach may not necessarily be a fan. Essential oils which have been reported to work well are:

  • Tea Tree oil
  • Mint Essential Oils (one can even buy mint fume machines that releases minty scents constantly).
  • Peppermint Oil
  • Catnip Oil
  • Lavender Oil

Use these by spraying cockroaches directly and onto the area your find them around the house. Use sparingly, since these scents can get really strong.

Herbs and spices like Mint Plants, Cinnamon are also effective at releasing scents that a cockroach will dislike.

If you have a cockroach infestation, a temporary solution is just that honestly – temporary – and shortly after things may just get really bad as these roaches multiply and use more and more of your food and water to survive. More lethal measures are necessary. Of course, you can just call pest control services – they kill roaches for a living and other things. But you’re reading this probably because you want to kill roaches on your own using what you have in your home. In the next section, we look into how to get rid of the roaches permanently by looking at what can really kill cockroaches.


What kills roaches instantly?

If a roach dranks bleach, it will kill them, but they don’t like the strong smell of bleach so it’s not something they’ll voluntarily do. Also leaving bleach around your house is dangerous for pets and children. So then, somehow you’ll have to find a way to use bleach safely and also make the roaches drink it, which is harder to achieve than it sounds. Just putting bleach on their skin will have little to no effect. The way bleach can kill roaches is by drowning them.

This method requires using some kinds of bait to catch the roaches and submerging them into the bleach or clorox (pure or solution). It’s quite difficult to do and is extremely inefficient given how fast roaches are. Also if you have a cockroach infestation, this could take forever. The best way of using bleach to get rid of cockroaches is to buy one of the spray bottles that are readily available and spray it around the roach nests. They are often found in pipes (caution: bleach is corrosive so pipes may get damaged from this) or wherever you see these creepy little critters crawl out of. This will draw them out and make it easier to kill through some other means. If you see cockroach eggs, remember to spray those too. Just be very careful handling bleach and always wear protective gloves.

Boric acid is probably a more effective cockroach killer. Boric acid is known to wear away the exoskeleton of cockroaches making them vulnerable and leading to their drying up really quickly. Use boric acid near places where cockroaches are known to pass through of like cracks and crevices and near plumbing. Fine dust sprinkles here and there should do. Make sure to not use near places where food is prepared though.


To summarise, we looked into the question “does bleach kill roaches”? We then found that the use of bleach is not exactly practical when it comes to killing roaches and even less efficient than many other methods out there. If you have a roach infestation it’s probably best to call pest control after trying roach killer pesticides or other natural/home solutions if the problem persists. Pest control guys will know what to do – they know the best methods to kill cockroaches quicky and safely.


Dave Campbell

I'm Dave Campbell and the owner of You can read more about me and my background on my About Me page.

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