How to Get Rid of Silverfish: Complete Guide for Homeowners

Last updated: March 4, 2026

By James — 25-year pest control industry veteran

Silverfish are one of the most common household pests, and figuring out how to get rid of silverfish can be frustrating because they are nocturnal, fast-moving, and capable of surviving for months without food. These small, wingless insects thrive in damp, dark environments and feed on starchy materials found in nearly every home. While they do not bite or spread disease, silverfish can damage books, clothing, wallpaper, and important documents if left unchecked.

This guide covers everything homeowners need to know about identifying silverfish, understanding why they invade homes, eliminating them with DIY methods, and knowing when professional treatment is the better option. For general pest control pricing, see our pest control cost guide.

What Do Silverfish Look Like?

Silverfish are small, wingless insects that are easy to identify once you know what to look for. Adults are typically 1/2 to 3/4 inch long with a distinctive teardrop-shaped body that tapers from head to tail. Their bodies are covered in fine, silvery-gray scales that give them a metallic, fish-like appearance, which is how they got their name.

They have two long antennae on the front of their head and three tail-like appendages (called cerci) at the rear. Silverfish move in a rapid, side-to-side wiggling motion that resembles a swimming fish. They are wingless at every life stage and do not fly or jump. Silverfish are often confused with firebrats, a closely related species that prefers warmer environments. The main difference is color: silverfish are silvery-gray, while firebrats are mottled brown.

Why Silverfish Are in Your Home

Silverfish enter homes seeking two things: moisture and food. Understanding what draws them in is the first step toward eliminating them.

Moisture and humidity

Silverfish require high humidity to survive, generally 75% to 90% relative humidity. Homes with damp basements, poorly ventilated bathrooms, leaky pipes, or condensation problems provide the moisture silverfish need. They are especially common in older homes where moisture control is limited. Even a consistently humid bathroom or a basement without a dehumidifier can sustain a silverfish population.

Starchy food sources

Silverfish feed on a wide range of starchy and sugary materials. Their diet includes paper, book bindings, wallpaper paste, cardboard, newspaper, photos, cotton and linen fabrics, starched clothing, dried pasta, cereal, flour, and even the glue used in packaging. Homes with large book collections, stored cardboard boxes, or paper clutter are especially attractive to silverfish.

Shelter and darkness

Because silverfish are strongly nocturnal and avoid light, they seek out dark, undisturbed hiding spots. Cluttered storage areas, stacked boxes, and seldom-moved furniture provide ideal harborage. They can flatten their bodies to squeeze into surprisingly tight cracks and crevices in walls, floors, and behind baseboards.

Common Hiding Spots

Knowing where silverfish hide during the day helps you target treatment efforts effectively. Check these locations when inspecting your home.

• Bathrooms. Under sinks, behind toilets, inside vanity cabinets, and in gaps around plumbing fixtures. Bathrooms without exhaust fans or with chronic moisture issues are prime silverfish habitat.
• Basements. Along foundation walls, in floor cracks, behind stored boxes, and near water heaters or laundry areas. Unfinished basements with exposed concrete are particularly attractive due to higher humidity levels.
• Attics. Around stored boxes of books, documents, or clothing. Attics with poor insulation can develop condensation that creates the humidity silverfish need, particularly during temperature swings.
• Behind wallpaper. Silverfish feed on wallpaper paste and the paper itself. Peeling or bubbling wallpaper can indicate silverfish activity behind it.
• Kitchens. Inside cabinets, behind appliances, under sinks, and in pantries near dry goods like flour, cereal, and pasta. Gaps around pipes provide entry points and hiding spots.
• Closets and bookshelves. Among stored clothing, in cardboard boxes, and between books. Silverfish feeding damage on clothing appears as small, irregular holes or surface scraping, particularly on cotton, linen, and silk.
• Wall voids and baseboards. Inside wall cavities accessed through cracks, gaps around electrical outlets, and spaces behind baseboards. These hidden areas can harbor significant populations that go unnoticed for months.

DIY Methods for Getting Rid of Silverfish

Most minor to moderate silverfish infestations can be managed with a combination of DIY methods. The key is reducing moisture, eliminating food sources, and using targeted treatments in the areas where silverfish are active.

Reduce humidity with dehumidifiers

Since silverfish depend on high humidity, running a dehumidifier in damp areas like basements, bathrooms, and laundry rooms is one of the most effective long-term control measures. Aim to keep indoor humidity below 50%. Fix any leaking pipes, improve bathroom ventilation with exhaust fans, and ensure proper drainage around your foundation. Reducing moisture alone can make your home inhospitable to silverfish over time.

Diatomaceous earth

Food-grade diatomaceous earth (DE) is a natural powder made from fossilized algae that damages the waxy coating on silverfish exoskeletons, causing them to dehydrate and die. Apply a thin, even layer in cracks along baseboards, behind appliances, under sinks, inside wall voids through electrical outlet gaps (with power off), and in other areas where silverfish travel. DE is non-toxic to humans and pets but should be applied lightly to avoid creating airborne dust. Reapply after vacuuming or if the powder gets wet, since moisture renders it ineffective.

Sticky traps

Flat sticky traps (also called glue boards) placed along baseboards, under sinks, behind toilets, and in closets can catch silverfish as they move along their regular pathways at night. Sticky traps are useful for monitoring the extent of an infestation and identifying which rooms are most active. Place them flat against walls where silverfish are likely to travel. Check and replace traps every one to two weeks.

Boric acid

Boric acid powder is an effective silverfish killer when applied in thin layers to cracks, crevices, and hidden areas where silverfish travel. Silverfish walk through the powder, ingest it during grooming, and die within a few days. Apply boric acid behind baseboards, in wall voids, under cabinets, and around pipe penetrations. Keep boric acid away from areas accessible to children and pets, and always follow the product label instructions.

Cedar shavings

Cedar shavings and cedar oil act as a natural repellent for silverfish. Place cedar shavings in closets, drawers, storage boxes, and other areas where silverfish are found. Cedar blocks or sachets placed among stored clothing and books can help deter silverfish from feeding on these items. While cedar alone is unlikely to eliminate an established infestation, it works well as a supplemental deterrent alongside other methods.

Seal cracks and entry points

Caulk cracks and gaps along baseboards, around window frames, door frames, and pipe penetrations to reduce silverfish hiding spots and limit their movement between rooms and wall voids. Pay special attention to bathrooms and kitchens where plumbing penetrations create gaps. Sealing entry points also helps contain silverfish to treated areas where they are more likely to encounter boric acid or diatomaceous earth.

Reduce food sources and clutter

Store paper goods, books, and documents in sealed plastic containers rather than cardboard boxes. Keep dry pantry goods like flour, cereal, and pasta in airtight containers. Remove old newspapers, magazines, and cardboard from storage areas. Reducing clutter eliminates both food sources and hiding spots, making your home less attractive to silverfish and making treatment more effective. For guidance on maintaining a pest-free home, see our article on how often to spray for pest control.

Why Silverfish Are Hard to Eliminate

Silverfish infestations often persist despite treatment efforts, and understanding why helps set realistic expectations and improve your approach.

Nocturnal behavior

Silverfish are strictly nocturnal and extremely fast-moving. They spend daylight hours hidden deep in wall voids, cracks, and other inaccessible areas. Most homeowners never see the majority of the silverfish in their home because the insects only emerge in darkness. This makes it difficult to gauge the true size of an infestation or verify that treatments are working without using sticky traps for monitoring.

Rapid reproduction

A single female silverfish can lay clusters of two to twenty eggs at a time throughout her life, depositing them in cracks, crevices, and behind objects. Eggs hatch in two to eight weeks depending on conditions. While silverfish reproduce more slowly than some pests, their long lifespan (two to eight years) means each individual contributes to the population for an extended period. A small population can grow steadily if conditions remain favorable.

Survival without food

Silverfish can survive for several months without eating, which means simply removing food sources will not eliminate an existing population quickly. They slow their metabolism in unfavorable conditions and wait for better opportunities. This resilience means that control efforts need to be sustained over weeks or months rather than relying on a single treatment.

Hidden nesting areas

Silverfish nest and lay eggs inside wall voids, beneath flooring, behind insulation, and in other areas that are nearly impossible to reach with surface treatments. Even thorough applications of dust or powder may not reach every nesting site. This is one reason professional treatments, which can inject products into wall voids and other hidden areas, are sometimes necessary for complete elimination.

When to Call a Professional

While DIY methods work well for small silverfish problems, there are situations where professional pest control is the more effective and cost-efficient option.

• The infestation is large or widespread. If you are seeing silverfish regularly in multiple rooms, the population has likely grown beyond what surface treatments can manage. Professionals can treat wall voids and hidden areas that DIY products cannot reach.
• DIY methods have not worked after four to six weeks. If consistent DIY treatment has not reduced silverfish activity within a month or more, the nesting sites are likely in areas you cannot access.
• Silverfish are causing property damage. Noticeable damage to books, documents, clothing, or wallpaper indicates a significant infestation that warrants professional intervention to prevent further loss.
• You have chronic moisture problems. Homes with ongoing moisture issues may need both a pest control professional and a plumber or waterproofing contractor to address the root cause.

For more guidance on making this decision, see our article on when to call an exterminator.

Professional Treatment Options

Professional pest control technicians have access to commercial-grade products and application methods that are more effective than consumer-grade options for silverfish. Here are the most common professional approaches.

Most professional treatments include a follow-up visit two to four weeks after the initial application to address any remaining silverfish that were in inaccessible areas during the first treatment. For a full breakdown of pest control pricing, see our pest control cost guide.

Prevention Tips

Once silverfish are eliminated, ongoing prevention keeps them from returning. These habits address the moisture and food conditions that attract silverfish in the first place.

• Maintain low indoor humidity. Keep humidity below 50% using dehumidifiers in basements and crawl spaces. Run exhaust fans during and after showers. Ensure dryer vents exhaust to the outdoors. Proper ventilation is the single most effective long-term silverfish prevention measure.
• Fix leaks promptly. Repair dripping faucets, leaking pipes, and any sources of water intrusion. Even small leaks under sinks or behind walls create the damp conditions silverfish need to thrive.
• Store items in sealed containers. Replace cardboard boxes in storage areas with plastic bins with tight-fitting lids. Store important documents, photos, and books in sealed containers. This removes both food sources and nesting sites.
• Keep dry goods sealed. Store flour, cereal, pasta, sugar, and other pantry staples in airtight containers rather than leaving them in original packaging that silverfish can chew through.
• Reduce clutter. Clear out old newspapers, magazines, and cardboard regularly. Declutter closets, attics, and basements to eliminate hiding spots and make it easier to detect silverfish activity early.
• Seal cracks and crevices. Caulk gaps around baseboards, windows, door frames, and plumbing penetrations. This limits silverfish movement and entry points, and makes any future treatment more effective by reducing harborage.
• Ventilate crawl spaces and attics. Ensure adequate airflow in crawl spaces and attics to prevent moisture buildup. Install vapor barriers over exposed soil in crawl spaces to reduce ground moisture entering the home.

Frequently Asked Questions