Silverfish control works best when you combine three steps: lower humidity with a dehumidifier or fan, remove food sources like paper and starchy fabric, and seal cracks around baseboards and pipes. Add diatomaceous earth or boric acid in hidden spots, and traps or baits for tougher infestations.
If you’ve ever flipped on a bathroom light at night and watched a small, silvery bug dart under the tub, you’ve met a silverfish. They’re fast, they’re creepy-looking, and they show up when you least expect them. The good news is that silverfish control isn’t complicated once you understand what draws them into your home in the first place.
This guide walks you through why silverfish show up, how to get rid of them fast, and what to do so they never come back.
What Silverfish Are and Why They’re in Your Home
Silverfish are small, wingless insects with a teardrop-shaped body that tapers from head to tail. Most measure between half an inch and three-quarters of an inch long. Their silvery, metallic scales and quick, fish-like movements give them their name.
These bugs are nocturnal, so you’ll rarely see them during the day. They hide in cracks, behind baseboards, and inside boxes, then come out at night to feed. Silverfish love starchy materials. That means book bindings, wallpaper paste, cardboard, cotton clothing, and even flour or cereal in your pantry are all fair game.
Moisture is the other big draw. Silverfish need humidity between roughly 75 and 97 percent to thrive, which is why bathrooms, basements, and attics are their favorite hangouts. A leaky pipe or a poorly ventilated closet can turn into a silverfish breeding ground without you noticing for months.
They also live a long time for an insect. A silverfish can survive up to eight years, and a single female can lay more than 100 eggs over her lifetime. That’s why a small sighting can quietly turn into a real infestation if you don’t act.
How to Get Rid of Silverfish Fast
If you’re dealing with an active problem, start with drying out the space. Run a dehumidifier in your bathroom, basement, or laundry room, and fix any leaky faucets or pipes right away. Silverfish can’t survive long in a dry environment, so this one step alone will push a lot of them out.
Next, clear out the clutter they’re hiding in. Old newspapers, cardboard boxes, and stacks of unused paper are basically silverfish buffets. Go through storage areas and toss what you don’t need. Move anything you’re keeping into sealed plastic bins instead of cardboard boxes.
Diatomaceous earth is one of the most reliable tools for silverfish control, and it’s safe to use around most households. This fine powder comes from fossilized algae, and it works by scratching through the silverfish’s outer shell, which dries the insect out and kills it. Sprinkle a light layer along baseboards, inside closets, and in cracks where you’ve spotted activity. Just avoid heavy piles, since a thick layer can actually repel insects instead of attracting them.
Boric acid works in a similar way and is another solid option for basements, crawl spaces, and other areas away from kids and pets. Sweep and vacuum the area first, then dust boric acid into the cracks and crevices where silverfish travel.
Store-bought traps offer a simple way to track and reduce a population without chemicals. Sticky traps placed along walls and in dark corners will catch silverfish as they move through the night. These traps also give you a good sense of how bad the problem actually is, since more silverfish in the trap means more of them nearby.
For a bigger infestation, insecticide sprays and foggers can help knock down numbers quickly. These products are effective, but they’re also strong, so keep them away from food prep areas, kids, and pets, and always follow the label instructions closely. Baits containing indoxacarb have also shown strong results in research settings, cutting silverfish populations by more than 90 percent over several weeks when used correctly.
Natural Silverfish Repellents Worth Trying
If you’d rather skip chemicals altogether, a few natural options can help keep silverfish away. Cedar chips and cedar oil have a scent that many insects, including silverfish, tend to avoid. Placing cedar blocks in closets or storage bins can make those spaces less appealing.
Citrus peels work in a similar way. Silverfish don’t like the smell of citrus, so leaving orange or lemon peels near entry points can act as a mild deterrent. It won’t wipe out an infestation on its own, but it’s a helpful add-on to your overall plan.
Essential oils like lavender and clove are also worth a try. Mix a few drops with water in a spray bottle and apply it around baseboards, window frames, and other spots where you’ve seen silverfish. Reapply every few days since the scent fades quickly.
None of these natural methods will solve a serious infestation by themselves. Think of them as support for the bigger strategy: cutting moisture, removing food sources, and sealing up entry points.
Sealing Entry Points and Preventing Future Problems
Once you’ve dealt with the silverfish that are already inside, the next step is making sure new ones can’t get in. Silverfish have thin, flexible bodies that let them squeeze through surprisingly small gaps, so sealing your home matters more than people expect.
Walk through your house and look for cracks around baseboards, window frames, and door frames. A tube of caulk goes a long way here, and it’s a quick weekend project. Add weatherstripping to doors and windows that don’t seal tightly, since these gaps are common entry points.
Pipes and utility lines need special attention because the openings around them are often bigger than they look. Stuff steel wool into these gaps before sealing them with caulk, since steel wool blocks pests that might otherwise chew through softer materials.
Check window screens for tears and patch or replace any that are damaged. Silverfish and other insects will find their way through even small holes, especially at night when they’re most active.
Keep an eye on humidity levels long-term, not just when you notice a problem. A hygrometer is a cheap tool that tells you the humidity in any room, and keeping levels below 50 percent makes your home far less inviting to silverfish. Good ventilation in bathrooms and kitchens, along with regular use of exhaust fans, helps keep moisture from building up in the first place.
When to Call a Pest Control Professional
Most silverfish problems can be handled with the steps above, but some situations call for outside help. If you live in an apartment building, silverfish can travel between units through shared walls and plumbing, which makes it hard to solve the problem on your own.
A heavy, ongoing infestation that doesn’t respond to traps, diatomaceous earth, or sprays after a few weeks is another sign it’s time to bring in a licensed pest control service. Professionals have access to stronger treatments and can also identify entry points you might have missed, especially in older homes with more cracks and gaps.
It’s also worth calling in help if you’re dealing with a related species like the long-tailed silverfish, which research shows is harder to eliminate than the common household variety. These pests tend to spread more evenly throughout a building rather than staying in one damp corner, so a broader treatment plan usually works better than DIY spot treatments.
Final Thoughts on Keeping Silverfish Away
Silverfish control comes down to making your home less appealing to them and backing that up with the right tools when needed. Dry out damp areas, clear away paper and cardboard clutter, seal up cracks, and use diatomaceous earth, traps, or targeted treatments where you’re seeing activity. Stay consistent with these habits, and you’ll keep your home a place silverfish want to avoid instead of one they want to move into.