What Time Do Roaches Go To Sleep?

As one of the hundreds of souls who have become victims to that natural creature with unnatural invulnerability, you’re probably thinking of ways you can eradicate cockroaches from your home. One of the things you need to know is when roaches are active.

The American cockroach, Periplaneta Americana, follows an internal twenty-four-hour circadian rhythm where they roam to find food, drink water, and reproduce with other cockroaches for four hours, and then return to their hiding places to rest for the next twenty hours.

The idea that roaches are only out for four hours must be pretty hard to believe for you thanks to the well-earned reputation of cockroaches being unstoppable swarms that appear everywhere at all times. But in spite of that reputation, cockroaches are actually pretty lazy. If you want to learn when your twenty-hour opportunity is for catching these creepy crawlies at their most vulnerable, then read on.

Do Cockroaches Sleep?

It might be a surprise to you that cockroaches sleep at all. Once your home is infested with cockroaches, they seem to be ever-present from that point on until you’re finally able to have them exterminated.

The fact is, cockroaches don’t sleep. At least, they don’t sleep in the sense we have always known sleeping to be. After all, they don’t have eyelids with which to shut.

However, according to the cockroach guide, cockroaches do follow a circadian rhythm. This means that they follow a pattern in their activity that repeats about every 24 hours. They have specified lengths of time dedicated to being active and then they go into dedicated periods of inactivity like we would normally do with true sleeping.

The difference is that their period of inactivity doesn’t send them into a sound slumber. Instead, they just become immobile for an extended period of time, which we’ll look at in more detail shortly.

When Do Cockroaches Sleep?

So when are cockroaches inactive? As nocturnal creatures, they fall into inactivity during the day to recuperate and renew their strength for the next evening. Still, even though we know that roaches have their circadian rhythm, having people who have seen these things at various hours makes us wonder if they have a strict rhythm and follow a regular schedule.

Do we need to worry about these things all hours of the night as some are awake and others aren’t, or can we expect them at a certain time? Afterall, we break our rhythm on a regular basis, so why not cockroaches?

Well, a study conducted by Shepherd K. Def. Roberts showed that the American cockroach – the cockroach most of us are familiar with and despise – has its circadian rhythm controlled via its brain, just like we do.

This means that specific functions in their body that pertain to eating, resting, and reproducing are controlled by the set cycles dictated by their brain. In humans, studies show that the hypothalamus in the brain is associated with our circadian rhythm because of the suprachciasmatic nucleus, which is connected to our optic nerves, and able to respond to the input of light and darkness.

If the cockroach’s internal “clock” functions similarly, then the absence of light in its eyes would prompt their equivalent of a suprachiasmatic nucleus to send signals to their body to start waking up and getting a move on.

The problem with this is that roaches hide in dark cavities, so how would constant darkness let them know it’s time to look for food and water? This suggests that cockroaches live by a consistent schedule because their brains have a strict circadian rhythm. This means you can also rely on a pretty faithful time that cockroaches come out.

What Time Do Cockroaches Come Out?

Now that we’ve established that cockroaches are nocturnal, we come to the aspect about cockroaches that make them sheer menaces. When do they actually invade your space?

Being active at night is a good way to protect themselves from potential threats like us, since these threats are asleep. It definitely isn’t their camouflage that helps them. Once they feel it’s safe to come out, they will be active in your home for about four hours to find food and water and also mate.

Cockroaches come out when you have turned out all the lights and go to bed. Their internal clocks are set to make sure they come out when the house is completely dark and quiet before beginning their nightly raid. Once they come out, they’ll only be scurrying about for four hours.

Four hours is all the time a cockroach needs to find food because they are genetically efficient at it/ What I mean is they have 150 olfactory receptors in their body that make it easy to sense where food is and 500 gustatory receptors that allow them to digest just about anything they find. These two receptors make it easy for these pests to find food, be it your dinner leftovers on dishes that you haven’t washed, rotting remnants in your garbage can, or one another if things get hard.

Depending on the size of the colony that has laid claim to your dwelling, you might find a few “scouts,” coming out to do their business or a swarm. When the cockroaches have come to the end of their four-hour workday, they return to their lairs in the cracks and crevices of your house and fall into another phase of immobility. Then the cycle repeats.

How Many Hours do Cockroaches sleep?

Since these nuisances actually have a reliable internal clock for us to estimate when they will come out, we can fairly estimate how long they sleep. Being only active for four hours, these literal buggers that plague the lives of homeowners, are asleep for 20 hours out of the day! That’s an unbelievable amount of time considering how much aggravation they’re able to cause you in the four hours they’re awake!

There are also some unanswered questions, like if roaches are only awake for four hours right after the sun goes down, then why do so many people encounter them at different times, or even during the day too?

Well, if you move about during the night to get a midnight snack, or because you need the bathroom, you can encounter them at varying times by disturbing the places where they were trying to hide, waking them up, and causing them to scurry.

As for the daytime, many victims of these insects have in fact seen them out during the daytime, and the reason for that resembles us when we wake up during the middle of the night for a midnight snack. Yep! When roaches don’t get enough food during their night excursions, they have to wake up and look again.

So, if you’ve been dealing with an infestation of cockroaches and you suddenly find them coming out during the day, this is actually a good sign. It means they’re not able to find food easily, which helps make your home unsuitable for them. However, don’t throw away the business card of your local exterminator yet, because a single cockroach can live several weeks to a month without food.


It’s pretty astounding that the American cockroach isn’t actually as hyperactive as it feels they are, isn’t it? In such a short amount of time, they are able to riddle our homes with filth. Of course, it is filth and moisture that attracts them, so if you do find them crawling around your floors and cabinets, consider really deep cleaning everything.

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