To get rid of millipedes, remove moisture and hiding spots around your foundation, vacuum up any indoors, and seal entry points like gaps under doors and foundation cracks. Diatomaceous earth and a dehumidifier handle most home infestations without chemicals.
You flip on the bathroom light at night and there they are. Long, worm-like bodies. Dozens of tiny legs moving in a slow wave across the tile. Your first thought is probably “what is that thing,” followed quickly by “how do I make it leave.”
Good news first. Millipedes won’t bite you, sting you, or chew through your walls. They’re not after your food or your furniture. But that doesn’t mean you want them setting up camp in your basement or curling into little balls on your bathroom floor. Here’s exactly how to get them out and keep them out.
What Millipedes Are and Why They End Up in Your House
Millipedes belong to a group of bugs called arthropods, and there are over 10,000 known species. Most of the ones you’ll see indoors are brown or black, one to two inches long, with a body made of many segments. Each segment carries two pairs of legs, which is where the “thousand legs” name comes from, even though most species have somewhere between 40 and 400.
They live outside in mulch, leaf piles, rotting logs, and damp soil, where they feed on decaying plant matter. That’s actually a useful job. Millipedes help break down organic material and return nutrients to the ground.
The trouble starts when the weather outside stops working for them. Heavy rain floods their usual hiding spots, so they crawl toward higher, drier ground. Sometimes that ground is your foundation. On the flip side, a stretch of dry weather can send them looking for moisture, and your damp basement or leaky bathroom pipe looks like an oasis. Either way, once they cross into your home, they usually can’t find their way back out, and they don’t survive long indoors since the air is too dry for them.
Signs You Actually Have a Millipede Problem
Most millipede issues are pretty obvious once you know what to look for. You might spot them moving across the floor at night, since they’re most active after dark. You might also find them curled into tight spirals in corners, which is what they do when they’re dying from dehydration.
Check basements, crawl spaces, bathrooms, and laundry rooms first, since these hold the most moisture in a typical home. A flashlight helps a lot here, especially if you’re checking after sunset. You may also notice small piles of shed exoskeletons in undisturbed spots, which usually means the population has been established for a while rather than just wandering in once.
Sightings tend to spike within a day or two after a big rainstorm, so if you notice a sudden cluster after wet weather, that timing itself is a strong clue.
Getting Rid of Millipedes Already Inside
Once millipedes are indoors, removing them is usually simple. A vacuum cleaner or shop vac works well for clearing out a group at once, and it’s the fastest option if you’re dealing with more than a few stragglers. Just empty or replace the bag afterward so they don’t crawl back out.
For smaller numbers, a broom and dustpan does the job fine. Millipedes move slowly and don’t put up a fight, so sweeping them into a bag and tossing them outside takes only a minute. Some people prefer picking them up by hand, which is safe to do, though wearing gloves is smart since certain species release a mild irritating fluid when they feel threatened.
If you’d rather not deal with live bugs at all, sticky glue traps placed along baseboards in damp rooms will catch them as they travel through your home.
Natural Remedies That Actually Work
If you want to avoid chemical sprays, several natural options do a solid job of both killing and repelling millipedes.
Diatomaceous earth is probably the most effective natural tool available. It’s a fine powder made from fossilized algae, and while it feels harmless to us, it’s abrasive enough to damage a millipede’s exoskeleton. That damage causes the bug to dry out and die within a day or two. Dust it lightly along baseboards, in basement corners, and around pipe entry points under sinks. A light layer works better than a thick one, since millipedes need to walk through it for it to work.
Essential oils are another solid choice, particularly peppermint and tea tree oil. Millipedes dislike the strong scent, so mixing a few drops with water in a spray bottle and misting it around doors, windows, and foundation cracks helps keep new ones from wandering in. Bay leaves work on the same principle and can be tucked into cabinets or corners where you’ve seen activity.
Salt sprinkled around entry points is another old trick that pest control folks still recommend, since millipedes avoid crossing it. Citrus peels contain natural oils that repel them too, and boiling the peels in water gives you a spray you can use the same way as the essential oil mix.
None of these natural methods work as fast as a chemical insecticide, but for the average home infestation, they’re usually enough on their own.
Cutting Off Their Moisture Supply
Here’s the part that matters most, and it’s also the part people skip. You can vacuum up every millipede in your house today, and more will show up next week if the conditions that drew them in are still there. Millipedes go wherever the moisture is, so drying out your home is the real long-term fix.
Start with a dehumidifier in your basement, crawl space, or bathroom, since these rooms usually run the most humid. Aim to keep indoor humidity between 30 and 50 percent, and a cheap hygrometer from any hardware store will tell you exactly where you stand. Exhaust fans in bathrooms and a ceiling fan or two for better airflow also make a noticeable difference over time.
Outside, walk your foundation and look for anything holding water against the house. Clean out your gutters and make sure downspouts push water at least a few feet away from the foundation instead of dumping it right next to the wall. Pull mulch back a few inches from your foundation, since a mulch bed pressed against the house is basically a millipede welcome mat. Rake up leaf litter and grass clippings near the base of your home too.
Inside, check for leaky faucets, dripping pipes under sinks, or anything else adding unwanted moisture to the air. Fixing even one small leak can make a real difference in how attractive your home is to these bugs.
Sealing Up Their Entry Points
Moisture control keeps millipedes from wanting to come in. Sealing gets rid of the ways they physically can.
Walk the outside of your house and look closely at your foundation for cracks, gaps, or crumbling mortar, then caulk anything you find. Check where pipes and wires enter the house, since these openings are common highways for small pests. Weather stripping under exterior doors closes off one of the most common entry points of all, and it’s a quick fix most people can handle in an afternoon.
Basement window wells deserve a look too, since millipedes often collect there before finding a crack to slip through. A little copper mesh or foam sealant in these gaps goes a long way toward keeping the problem from returning next season.
When to Bring in a Professional
Most millipede problems clear up with the steps above, usually within a few weeks. If you’ve handled the moisture issues, sealed the obvious gaps, and you’re still seeing regular activity, that usually points to something bigger, like a crawl space drainage issue or a larger outdoor population right next to your foundation.
At that point, a pest control professional can pinpoint exactly where they’re getting in and apply a perimeter treatment that lasts longer than most DIY sprays. This is especially worth considering if you live in a region with heavy spring or fall rains, since millipede activity there tends to follow a predictable seasonal pattern year after year.
Millipedes are one of the more forgiving pests to deal with. They won’t damage your home, and once you dry things out and block their way in, they generally stay gone for good.