The centipede you’re most likely encountering in Michigan is the house centipede (Scutigera coleoptrata), a fast-moving, long-legged arthropod that thrives in damp basements, crawl spaces, and bathrooms. It’s the most common centipede found in Michigan homes and the only species in the state capable of reproducing indoors. While startling to spot darting across your floor at night, house centipedes are largely harmless and actually serve as pest control, feeding on insects you’d rather not have around.
What House Centipedes Look Like
House centipedes are distinctive once you know what to look for. They have long, flattened bodies with 15 pairs of legs that extend out to the sides, giving them a feathery, almost eyelash-like appearance. Those legs get progressively longer toward the back of the body, which helps them move at surprising speed across walls and floors. Their coloring is yellowish-gray with dark stripes running down the body.
People sometimes confuse centipedes with millipedes, but the two are easy to tell apart. Centipedes have one pair of legs per body segment, positioned on the sides, while millipedes have two pairs per segment tucked directly underneath. Centipedes are flat; millipedes are rounded. When threatened, a millipede curls into a ball and releases a foul-smelling secretion. A centipede bolts. Both have poor eyesight and navigate primarily by sensing vibrations.
Why They’re in Your House
House centipedes need two things: moisture and prey. They’re nocturnal hunters that spend the day hiding in dark, damp spots and emerge at night to feed on silverfish, carpet beetle larvae, cockroaches, spiders, and other small arthropods. If you’re seeing centipedes frequently, that’s actually a signal worth paying attention to. It often means another pest population in your home is large enough to sustain them.
Michigan’s climate, with its humid summers and cold winters, drives centipedes indoors in search of stable, moist environments. They find their way in through expansion cracks in concrete slabs, gaps around sump pump openings, uncapped cement blocks, missing mortar joints, and pipes that pass through walls. Floor drains without water traps, especially those connected to dry sumps, are another common entry point. Once inside, they gravitate toward basements, crawl spaces, and any area where cardboard boxes sit on concrete slabs.
Can Michigan Centipedes Bite?
House centipedes can technically bite, but they rarely do, and the result is typically mild. What’s commonly called a “bite” is actually a pinch from modified front legs called forcipules, which pierce the skin and deliver a small amount of venom. For house centipedes, this usually produces nothing more than minor, localized pain similar to a bee sting, along with some redness and swelling that resolves within a few days.
Larger tropical species in the Scolopendra genus can cause more serious reactions, including intense pain, swelling, numbness, tingling, headache, nausea, and occasionally fever. But those species don’t live in Michigan. The house centipedes you’ll find here are small enough that their forcipules often can’t even penetrate human skin effectively. If one does get you, clean the area with soap and water and apply a cold compress. The discomfort typically fades quickly.
How to Reduce Humidity and Remove Entry Points
Since moisture is the primary factor drawing centipedes indoors, controlling humidity is the single most effective strategy. A dehumidifier that keeps indoor levels between 30% and 50% makes your home far less hospitable. Fix plumbing leaks promptly, and wrap cold-water pipes that collect condensation in humid weather. Run bathroom exhaust fans for at least 20 minutes after showers, and confirm they vent to the outside rather than into your attic.
Sealing entry points cuts off the supply of new centipedes migrating in from outdoors. Check around basement windows, pipe penetrations, door thresholds, and the junction where the rim joist meets the sill plate, a spot that’s frequently overlooked. Use exterior caulk for cracks under a quarter inch and low-expansion foam for larger gaps. Brush-type door sweeps and 20-mesh screens on foundation vents add another layer of protection.
Outdoor Changes That Make a Difference
What’s happening immediately around your foundation matters. Grade the soil so it slopes away from the house for at least 10 feet, directing water away rather than letting it pool against the walls. Keep gutters clean and extend downspouts well away from the foundation. These steps reduce the moisture that centipedes rely on in the soil near your home.
Create a 3-foot plant-free buffer zone around the perimeter. Replace wood mulch with gravel or stone, which dries faster and offers fewer hiding spots. Remove leaf litter, grass thatch, and decorative timbers from along the foundation. Prune shrub canopies so they sit at least 12 inches away from exterior walls. All of this eliminates the damp, sheltered microhabitats where centipedes congregate before making their way inside.
Getting Rid of Centipedes Already Inside
For centipedes that have already set up residence, a vacuum is your most immediate tool. House centipedes dry out quickly when indoor humidity drops below 40%, so reducing moisture alone will thin their numbers over time. Sticky traps placed along baseboards help you identify where activity is concentrated and catch centipedes passively.
Diatomaceous earth and silica gel dusts work by dehydrating centipedes that crawl through treated areas. Apply thin layers in wall voids, around sill plates, and inside pipe chases. Boric acid dust in wall voids and around entry points provides longer-lasting control. For outdoor perimeter treatment, products containing cyfluthrin or deltamethrin can be applied to areas where centipedes are active, though targeted application works better than broad spraying.
The most important thing to remember is that centipedes are a symptom, not just a problem on their own. If you’re seeing them regularly, investigate what they’re eating. Addressing the underlying prey population, whether it’s silverfish, cockroaches, or carpet beetles, removes the food source that’s sustaining them and solves two pest problems at once.