What Kills Cockroaches Instantly? 11 Methods to Try

Horror stories about cockroaches can make it seem like these pests are borderline immortal. In reality, learning what kills cockroaches instantly can make exterminating cockroaches easier and restore peace, sanity, and sanitation in your home.

The most effective methods for killing cockroaches include Borax applications, bait stations, diatomaceous earth, insect growth regulators, and more. Follow this guide to surefire ways to get rid of roaches.

Why You Have a Cockroach Infestation

Are you suddenly noticing cockroaches in your home? That’s a sign that an infestation is on the rise, and the roaches you don’t see are the real problem, since they’re busy breeding and building their numbers. 

Here are common reasons for roach infestations:

• Open access points: In many cases, a new wave of roaches means they found a way inside your home. Common culprits are insulation gaps or a widening gap around plumbing. 

• Roach infestation in connected living space: Cockroaches are a persistent issue in multi-living buildings, where one apartment will be infested and the roaches naturally find their way over to the next apartment.

• They stowed away in packages or suitcases: Cockroaches are often smuggled into new homes in packaging that’s infested, like furniture, appliances, or cartons of produce. They can also climb aboard suitcases and bags left in infested areas. 

• Untidy home: Cockroaches are attracted to debris, especially edible debris. If you have growing toddlers or recent new pets (or a new roommate), your home may have gotten a lot dirtier with leftover food bits, which brings in the roaches looking for snacks. 

• Undetected leaks: Cockroaches are attracted to water, so they love to converge around leaks hiding in your home. If your plumbing has encountered issues like leaks (or related humidity issues), it could have jumpstarted the infestation. 

1. Borax

Borax is considered the quintessential cockroach killer. Also known as sodium tetraborate, this substance exterminates cockroaches by dehydrating them. A little-known fact about cockroaches is that their exoskeletons become dehydrated very easily.

When using borax to wipe out cockroaches, sprinkle some of the powder substance in areas where roaches have been seen lurking. They’ll walk through it, track it back to a hiding spot, and potentially spread it to others. In addition to killing cockroaches, this handy substance can also help to eliminate bed bugs, ticks, lice, spiders, beetles, fleas, and flies.

Some of the downsides of using borax to eliminate cockroaches is that it doesn’t work on eggs, takes up to three days to work, and can pose health risks to pets and children. Plus, sprinkling Borax on your floors or other surfaces can get messy, and can cause skin irritation if anyone comes in contact with it.

2. Boric Acid

Many people use boric acid and borax interchangeably even though they are different. While borax is the unadulterated form that's taken right from the ground, boric acid is extracted for processing and refinement.

Like borax, boric acid kills cockroaches by dehydrating them. After rolling around in boric acid, a cockroach will ingest the poisonous material while preening its body. However, this method takes about three days to work, and often requires several treatments.

Plus, boric acid is very dangerous to humans if ingested, causing acute poisoning that results in diarrhea, vomiting, and stomach pain if ingested. Boric acid burns are possible with skin contact, as well as eye and skin irritation. So, sprinkling it around your home to kill roaches will require removing pets and children from the area.

3. Bait Stations

If waiting three days for cockroaches to die sounds like an eternity, consider using bait stations. Bait stations are long tubes filled with poison that broadcast enticing smells to cockroaches. Once a roach consumes the poison in the tube, it will travel back to its home to die.

When the other roaches eat that infected roach after its death, they will also become poisoned.

Bait stations work fast and are very effective, but they are risky to use in homes with pets and children. While most bait stations aren’t lethal to pets, they can seriously harm them if they ingest the station or the dead roach.

4. Gel Bait

While this eradication method takes a bit longer to work, it’s relatively easy to apply and there are many available options. Simply add small dots of gel bait in areas frequented by cockroaches, such as inside kitchen cabinets or near plumbing, and wait for it to trap and effectively kill the roaches. This method is a good long-term solution for a minor infestation.

5. Diatomaceous Earth

Diatomaceous earth is made of microscopic, fossilized creatures. It looks like gray dust, but to bugs, it’s a razor-sharp minefield. That makes it a powerful barrier against cockroaches, preventing them from accessing food and the undersides of appliances. 

While diatomaceous earth can kill cockroaches effectively, they typically avoid it. To get rid of cockroach infestations entirely, it’s important to use other methods, too. Fortunately, diatomaceous earth is inexpensive, non-toxic and safe to use in the kitchen—but it can be an irritant to pests and spread around easily. 

6. Petroleum Jelly

Petroleum jelly and similar substances aren’t exactly toxic for cockroaches. However, it is very sticky, which makes it a popular option for cockroach traps, including homemade traps some prefer to use over store-bought versions. DIY traps often lure cockroaches with some type of bait or old food. The jelly then traps them inside for easy disposal. 

7. Bleach

Bleach is a harsh chemical and not very friendly for any living organism. Cockroaches are no exception, and direct contact with a bleach solution will poison them quickly while burning through their shell. 

However, we advise against using a bleach solution if possible. This powerful chemical isn’t something you want to spray around kitchens and pantries. Also, don’t forget bleach’s ability to, well, bleach: It could leave you with whitened stains where you spray it. 

8. Soap and Water

Soap and water kills cockroaches instantly by suffocating them, as the chemicals in the soap cause reactions on their exoskeleton, leaving them vulnerable by breaking down their waxy protective layer. Mix equal parts dishwashing liquid and water in a spray bottle and spray directly onto cockroaches. Soapy water is only effective when directly sprayed onto the insect.

9. Baking Soda

Baking soda kills cockroaches by damaging their system through a buildup of gas in their stomachs. Mix equal parts sugar and baking soda and place on a piece of food, cardboard or paper or place it in a shallow dish in areas where roaches live. Once they consume the mixture with water, they die; however, they can develop a distaste for sugar over time, and this can be passed down to their offspring. 

10. Insect Growth Regulator

You can buy products called insect growth regulators (IGRs) designed to hamper insect infestations by targeting cockroach eggs and nymphs. This method is important because killing all of the adult cockroaches in your home won't be enough to stop an infestation if they've already reproduced. That’s why using boric acid isn't always enough to clear an infestation.

The most common IGR is a spray made with a pesticide called Pyriproxyfen, which cuts off infestation cycles by killing roaches at the earliest stages. Keep in mind that it doesn't kill adult cockroaches.

11. Roach Bombs 

While roach bombs or foggers can kill cockroaches, you should avoid using this method at all costs. Foggers throw pesticide into the air, dispersing toxic substances inside your home. Activating one can also be dangerous to the homeowner because you are in an enclosed space with very hazardous and flammable materials. Instead of using a roach bomb, contact a professional exterminator to determine the best course of eradication for your home.

When To Hire an Exterminator

Learning how to get rid of roaches can be useful when you see a stray intruder once in a while. However, a serious infestation requires effective results from a professional pest-management company. Roach experts have the tools to quickly kill roaches without creating risks or inconveniences for your household.

With the average cockroach exterminator cost falling between $100 and $600, the peace of mind is more than worth it. Of course, using natural roach repellant to deter roaches from even entering your home is a good starting point, but it may not eliminate the problem as quickly or efficiently as you would prefer.

Ultimately, your local bug exterminators will know exactly what kills cockroaches instantly in their favorite hiding spots. Get multiple quotes from pest control professionals to determine the best course of action for eliminating your home’s infestation.

How to Prevent Cockroach Infestations

Several practices can make sure that roaches stay away—or never become a problem in the first place. Here’s what to keep in mind:

• Maintain a well-sealed home: Good insulation practices and keeping an eye on the details help prevent cockroaches from getting inside. A professional inspection can help find hidden issues. 

• Adopt a “no crumb” policy: Tidy up after every meal, rather than letting food sit around or in the sink. Clean and sweep, especially after snacktime, and make sure no bits of food are left on the floor. Keep food tightly enclosed in pantries and cupboards, and regularly clean under the refrigerator and oven, too. 

• Tackle roach problems fast: Once you spot a few roaches, it’s time to act. The roaches you don’t see could be busy multiplying. Set simple bait traps, and if roach problems persist, contact a pest control pro quickly to apply more advanced solutions. 

• Lower the indoor humidity: Indoor humidity can be naturally high, especially in basements and attics that are poorly sealed. You can fix these issues by increasing ventilation in these areas or use technology to draw water away and make your home less appealing to cockroaches.

• Clean up junk and weeds around the house: Roaches like to stay hidden as they approach a house. If the several feet around your walls and foundation are clear, they’re much less likely to look for entryways inside. Clear up weeds, leaves, grass and anything else that’s collected against your home’s exterior. 

• Talk to pros about an exterior barrier spray: Some barrier sprays last for weeks or months and can help deter roaches from entering while you deal with the ones inside. 

• Clean up boxes and bags quickly: Throw away or recycle boxes or bags as soon as you can to eliminate hiding spots for roaches and reduce clutter.

DIY vs. Hiring a Pro

If you’re dealing with a major cockroach infestation, it’s best to hire a professional exterminator. Cockroach removal pros have the skills, tools, and knowledge to identify the cause of an infestation, apply treatments, and put preventative measures in place. An extermination visit costs around $200, but varies depending on the extent of the infestation and resulting treatment method.

If you want to try to resolve minor infestations on your own, you can buy your own bait traps and place them where cockroaches hide, like under appliances and in crawlspaces. Bait traps only cost around $20 to $50, but you’ll have to continue monitoring the problem yourself.