House Centipedes: What to Know

Medically Reviewed by Poonam Sachdev on January 16, 2023
4 min read

If you’re someone who can’t stand the sight of worms or cockroaches, or if you have arachnophobia, chances are you won’t appreciate having house centipedes around you, either. House centipedes are common household insects known for their many legs that help them scurry past you in the blink of an eye. Although house centipedes don’t pose a threat to humans and don’t typically harm infrastructure, seeing them in your home can be alarming.

Read on to learn more about where house centipedes come from, what they look like, and what they eat, as well as what you can do to prevent a house centipede infestation and how to get rid of them.

The house centipede (Scutigera coleoptrata) is the most common centipede found in the U.S. These centipedes are sometimes referred to as “hundred-leggers,” due to their many pairs of legs. House centipedes are usually about an inch or two long. Their bodies are divided into 15 segments, each with a pair of long legs. Other species of centipedes have more legs, but they always have an odd number of pairs of legs.

Centipedes are generally dark brown or yellow and sometimes have darker colors and markings. Adult centipedes have three dark parallel lines running from their head to the rear end of their bodies and a hair-covered pair of antennae on their heads. While some centipede species have compound eyes containing up to 200 optical units, others have a few simple eyes on each side of the head. Some centipedes don’t have any eyes.

House centipedes have a pair of legs called forcipules right below their mouths, converted to carry out pincer-like actions. They use these pincer-like legs to discharge a venomous sting at their prey or use it for self-defense. The pair of legs at the end of centipedes’ bodies is very long and resembles the antennae in front. This makes it tough for the centipede’s prey to differentiate the front from the rear.

Although they can look disgusting to some, they don’t harm humans. On the contrary, they help you by preying on other common household pests such as cockroaches, silverfish, firebrats, carpet beetle larvae, spiders, termites, bed bugs, and other small arthropods. Their long legs allow them to run fast as they chase their prey, pounce on them, and wrap their long spindly legs around them, preventing them from escaping.

House centipedes have three life stages — egg, larva, and adult. They generally spend the winter outdoors. They lay their eggs in summer. Female house centipedes prefer the soil, where they can lay up to 35 eggs over a few days.

Newly hatched larvae, which are rarely seen, have four pairs of legs. The larvae undergo six molts and gain new pairs of legs after every molt. For example, centipedes will have 5, 7, 9, 11, and 13 pairs of legs respectively after each molting stage, while after the final molt, they have 15 pairs of legs. They undergo four post-larval instars before reaching maturity.

The most common hideouts of house centipedes are damp and cool spots such as those in basements, closets, bathrooms, potted plants, unexcavated areas under the house, and under the bark of firewood stored indoors. Centipedes usually don’t move through drain pipes.

Centipedes are nocturnal creatures that hide in dark, damp, and cool places during the daytime and venture out in the dark to hunt. House centipedes also thrive outdoors and live under logs, rocks, and fallen tree bark.

Since centipedes are nocturnal, it can be tough to determine whether you have them in your house. One of the first signs of a centipede infestation is seeing them regularly in your home. But this could signify the presence of other arthropods or pests that are prey for the house centipede–a sign of a bigger problem.

If you’re already facing a pest infestation with the likes of cockroaches, termites, and spiders in your house, the chance of having house centipedes is higher. Basements or other damp and dark areas in your house that don’t see much activity are a perfect place for house centipedes to thrive.

While house centipedes themselves do not pose health risks, their presence indicates that there are other pests around.

House centipedes don’t harm or destroy stored products, fabrics, pets, humans, or the structural integrity of your building and are generally only considered a nuisance. All house centipedes are venomous, but they typically run away from humans, and they very rarely bite. Even if house centipedes bite you, it’s considered harmless.

Because house centipedes help you control infestations of other, more bothersome pests, there’s little reason to exterminate them. Pesticides are of limited effectiveness in eliminating house centipedes. With their long legs, they hold their bodies high when they move, allowing them limited contact with pesticide-laden surfaces, making most pesticides less effective.

The best way to control their numbers is by reducing the humidity in the open areas of your house, such as by activating dehumidifiers and fans.
In your basement, eliminate spots and fill in cracks and crevices around the walls. Keeping your basement neat also helps prevent the collection of damp spots around boxes and other items, which could attract these creatures.

Although you may not like the sight of house centipedes, they can be helpful in controlling more concerning pests. Getting rid of other pests from your house will go a long way toward reducing the number of house centipedes you see.