Several centipede species live throughout Tennessee, and most are harmless creatures you’ll find under rocks, in leaf litter, or occasionally darting across a basement floor. The most common indoor species is the house centipede, a fast-moving, long-legged predator that looks far more alarming than it actually is. Understanding what you’re dealing with helps you decide whether to leave them alone or take steps to keep them out.
Species You’re Most Likely to See
Three centipede types show up regularly in Tennessee homes and yards. The house centipede is the one most people encounter indoors. It has a dirty yellow body with three dark stripes running lengthwise, 15 pairs of banded legs, and long antennae. Adults are only about one to one and a half inches in body length, but those trailing legs and antennae make them look three to four inches long. They’re startlingly fast.
The brown centipede (sometimes called the stone centipede) is a smaller, darker species roughly one inch long. You’ll find it under stones, logs, and garden debris rather than inside your house. It’s a common garden predator across the eastern United States.
The largest species in the region is the Eastern bark centipede, which can reach about three inches in length. It’s a reddish-brown, robust centipede that lives under loose bark and in rotting wood. Despite its size, encounters with this species are uncommon because it stays well hidden outdoors. Most centipedes you’ll find in Tennessee are considerably smaller, typically half an inch to an inch.
Why House Centipedes Show Up Indoors
House centipedes are nocturnal hunters. During the day they hide in dark, damp spots, then come out at night to chase down prey: silverfish, carpet beetle larvae, cockroaches, spiders, and other small arthropods. In that sense, a house centipede in your basement is acting as free pest control.
They get inside through expansion cracks in concrete slabs, gaps around sump pump openings, uncapped cement blocks, missing mortar joints, pipes that pass through walls, and floor drains without water traps. Once inside, they gravitate toward crawl spaces, unfinished basements, bathrooms, and areas under cardboard boxes sitting on concrete. Females can live several years and produce up to 150 offspring over a lifetime, so a single centipede finding a comfortable spot can eventually lead to a noticeable population.
When Centipedes Are Most Active
Centipedes breed in spring and are most active during warm, humid months. Tennessee’s hot, humid summers create ideal conditions both outdoors and in poorly ventilated basements. You’re most likely to spot them from late spring through early fall. During dry spells or cold snaps, they push indoors seeking moisture and stable temperatures. Outdoors, they shelter in rotting logs, under stones, in leaf piles, and in grass clippings.
Centipede vs. Millipede
Tennessee has plenty of millipedes too, and the two are easy to confuse at a glance. A few quick differences:
- Legs per segment: Centipedes have one pair per body segment. Millipedes have two or four.
- Body shape: Centipedes are flat. Millipedes are cylindrical or slightly rounded.
- Speed: Centipedes move fast. Millipedes are slow, with legs rippling in a wavelike motion.
- Defense behavior: Centipedes never coil up. Millipedes curl into a tight spiral when disturbed.
- Biting: Centipedes can bite. Millipedes cannot, though some species release a defensive liquid that irritates skin or eyes.
- Diet: Centipedes are predators that eat other insects. Millipedes feed on decaying plant matter.
If you see a slow, round-bodied creature curled up under a flower pot, that’s a millipede. If something flat and leggy sprints across your bathroom tile, that’s a centipede.
Do Centipede Bites Hurt?
Centipedes inject venom through a pair of modified front legs called forcipules. For the species found in Tennessee, a bite typically causes intense but short-lived pain at the site, along with redness, swelling, and sometimes a burning or tingling sensation. The venom triggers pain through the same receptor your body uses to detect heat from chili peppers, which is why bites can feel like a sharp burn.
Most bites resolve within a few hours to a few days without lasting effects. Swelling, numbness, and tenderness around the bite are normal. Less commonly, people report headache, mild nausea, dizziness, or a general feeling of being unwell. Serious reactions are rare with the small species found in Tennessee, but they can happen in people who are allergic to insect venom. Signs of a dangerous reaction include difficulty breathing, wheezing, swelling of the tongue or throat, persistent dizziness, or hives spreading beyond the bite area.
For a typical bite, applying a cold pack to reduce swelling is the standard first aid. Clean the area with soap and water, and monitor for signs of infection over the next couple of days.
Keeping Centipedes Out of Your Home
Because centipedes need moisture and prey to survive indoors, removing both is the most effective long-term strategy.
Control Moisture
Fix leaking pipes and faucets, especially in basements and crawl spaces. Run a dehumidifier in damp basement areas. Use exhaust fans in bathrooms and attics to pull out excess humidity. If your crawl space has exposed earth, a vapor barrier can make a significant difference.
Seal Entry Points
Caulk cracks and gaps in your foundation, around window and door frames, and where utility pipes enter the house. Repair torn window screens and add weatherstripping to exterior doors. Cap open cement blocks in foundation walls. Make sure floor drains have functioning water traps, since dry drains are an open highway for centipedes.
Remove Food and Shelter
Centipedes follow their prey. If you reduce populations of spiders, silverfish, and cockroaches, centipedes lose their reason to stay. Clear clutter from basements, crawl spaces, and attics. Store items in sealed plastic bins rather than cardboard boxes sitting directly on concrete. Outside, move firewood, leaf piles, and mulch away from your foundation.
Perimeter Treatment
An insecticide barrier applied around your home’s exterior perimeter, along baseboards, and around door and window casings can help reduce entry. Both granular and spray formulations designed for home perimeter use are widely available. Reapply according to the product’s label, especially after heavy rain.
A single centipede sighting usually doesn’t signal an infestation. But if you’re seeing them regularly, that points to a moisture problem or an existing pest population that’s sustaining them. Solving those root issues does more than any spray alone.