How to Get Rid of Silverfish in Your Bathroom

Eliminate silverfish by reducing moisture, sealing entry points, using diatomaceous earth or boric acid, and maintaining regular cleaning routines.

1. Spot the Hidden Invaders. Look for silverfish in dark, damp spots like behind the toilet, under the sink, around the bathtub, and in corners where moisture collects. Check for their distinctive silver-gray insects about half an inch long, or look for their shed skins and small holes in paper products or fabrics.
2. Dry Out Their Habitat. Install or improve bathroom ventilation with an exhaust fan rated for your bathroom size. Run the fan during and after showers for at least 30 minutes. Fix any leaky pipes, faucets, or toilet seals immediately. Wipe down wet surfaces after use and consider a small dehumidifier if moisture problems persist.
3. Lock Down All Gaps. Use caulk to seal gaps around pipes, baseboards, and fixtures where silverfish might enter. Check and repair loose tile grout, especially around the tub and shower. Install door sweeps if there are gaps under bathroom doors.
4. Deploy the Powder. Sprinkle food-grade diatomaceous earth in thin lines along baseboards, behind the toilet, and in other areas where you've seen silverfish activity. The powder damages their exoskeletons and dehydrates them. Reapply after cleaning or if it gets wet.
5. Poison the Population. Mix boric acid powder with a small amount of sugar to create bait stations in bottle caps or small containers. Place these in corners and behind fixtures where children and pets cannot reach them. The silverfish will consume the mixture and die within days.
6. Starve the Problem. Store toiletries, medications, and any paper products in sealed plastic containers. Remove old magazines, newspapers, or cardboard from the bathroom. Clean up hair, soap residue, and other organic matter that silverfish feed on.
7. Catch What Remains. Place silverfish sticky traps along walls and in corners to catch remaining insects and monitor the effectiveness of your treatment. These work especially well behind the toilet and under the sink where silverfish commonly travel.
8. Keep Winning Long-Term. Vacuum the bathroom weekly, paying attention to corners and cracks. Mop with a mixture of water and a few drops of dish soap. Keep the bathroom as dry as possible between uses and immediately address any new moisture issues.