If you have house centipedes, you have something for them to eat.
House centipedes are predators. They eat silverfish, spiders, cockroach nymphs, carpet beetle larvae, and other small insects, and they settle in damp spaces where that prey is available. Alarming to find in a basement at midnight, genuinely harmless, and reliably an indicator of two things: humidity, and an insect population you may not have known about.
What their presence tells us
A centipede call is usually two investigations — the centipedes, and what they're hunting.
- Sightings in basements, bathrooms, and utility roomsCool, damp, dark spaces with insect traffic. Their preference for these areas is consistent enough to be diagnostic.
- Fast movement along floors and walls at nightThey're nocturnal, and remarkably quick. Most sightings happen when a light goes on suddenly.
- Presence of prey insectsSilverfish, spiders, small flies, and carpet beetle larvae. When we find centipedes we look for what's sustaining them, because that's the more actionable problem.
- High relative humidityThey lose water rapidly and can't persist in dry conditions. Sustained dampness in a basement or crawl space is nearly always part of the picture.
- Entry at grade and around plumbingFoundation cracks, utility penetrations, sump pits, floor drains, and gaps around basement window frames.
- Clutter and stored cardboardProvides both harborage for them and habitat for the insects they're eating.
How we handle house centipedes
- Identify and address the prey populationThis is the first move, not an afterthought. Removing the food supply is what makes a centipede problem resolve rather than recur.
- Reduce humidityDehumidification in basements and crawl spaces, correcting exterior drainage, insulating sweating pipes, and improving ventilation. Below fifty percent relative humidity the environment stops supporting them.
- Remove harborageClearing stored cardboard, lumber, and debris from basement floors and crawl spaces, and getting stored items up off the slab.
- Seal entry pointsFoundation cracks, gaps around utility penetrations, basement window frames, and sump and floor drain covers.
- Targeted treatment where warrantedCrack-and-crevice application and desiccant dust in voids and along foundation walls. We treat where they harbor rather than broadcast across open floor.
They're on your side, technically
House centipedes are among the few household arthropods that are genuinely beneficial indoors. They actively hunt and consume the pests most homeowners actually care about. Some people, once they know this, decide to leave them alone — and that's a defensible choice. Most people find them unsettling enough that it isn't, which is equally reasonable. We'll treat them if you want them gone; we'll also tell you honestly that they aren't hurting anything.
Can they bite?
Technically yes, though it's rare and requires handling one. They have modified front legs that deliver venom to subdue prey, but the structures usually can't penetrate human skin, and where they do the result is comparable to a mild bee sting with no lasting effect. They're not aggressive, they're not dangerous, and they have no interest in people.
Why treating only the centipedes doesn't hold
Because they're a secondary pest. Kill every centipede in a damp basement that still contains silverfish, spiders, and small flies, and more centipedes will find their way in over the following season. The prey population and the humidity are the actual problem; the centipedes are the visible consequence. This is why our approach here overlaps heavily with our silverfish and spider work.
Where we provide this service
Northport, East Northport, Huntington, Halesite, Centerport, Greenlawn, Cold Spring Harbor, Fort Salonga, and the surrounding North Shore communities. See all service areas.
Not sure what you're dealing with?
Send a photo by text and we'll tell you what it is. Identification is free, and it's the step that determines everything else.