22 Common Bugs in the Basement (& How to Get Rid of Them)

Your basement can easily become a haven for bugs if you’re not careful. The humid, dark environment is ideal for many creepy crawlies looking for food and shelter. Unfortunately, once these pests make themselves at home they can be very difficult to fully eradicate.

Knowing how to identify and handle a basement bug problem is key for every homeowner. In this guide, we’ll cover the 22 most common basement bugs, why they’re attracted to basements, and how to get rid of them for good.

Why Bugs Love Basements

There are a few key reasons bugs are drawn to basements:

Food – Bugs need to eat too! Basements often have plenty of food sources from stored pet food to cardboard boxes Pests like cockroaches and silverfish will eat almost anything

Water – Basements tend to be damp humid environments – perfect conditions for moisture-loving bugs. Leaky pipes and poor ventilation exacerbate wet basement problems.

Clutter – The stacks of boxes, old furniture, and general disorder found in many basements provide the perfect hiding spots for bugs.

Cracks – Gaps in the foundation walls or around pipes give insects an easy way to access your basement. Small openings are like highways for ants and other bugs.

Warmth – Basements maintain relatively stable, moderate temperatures all year round (50-70°F). Bugs want to escape extreme outdoor heat and cold.

22 Common Basement Bugs

Here are the bugs you’re most likely to encounter in the basement:

1. Cockroaches

Appearance: Reddish brown, flat, oval-shaped insects up to 1.5 inches long.

Threat: Cockroaches can transmit bacteria like Salmonella and E. coli. They leave droppings containing allergens.

Food: They eat almost anything including grease, paper, cardboard, books, and decaying matter.

Prevention: Eliminate moisture, seal cracks, remove clutter and food sources like cardboard, don’t leave pet food out.

2. Ants

Appearance: Very small (1/16-1/2 inch long) six-legged insects, often reddish-brown or black.

Threat: Some ants bite, but the main issues are contamination of food and annoyance.

Food: Ants feed on sugary substances, proteins, fats, dead insects, seeds.

Prevention: Seal cracks, eliminate moisture, store food in airtight containers, use ant baits.

3. Spiders

Appearance: 8 legs, 8 eyes, two body segments, come in many colors/sizes.

Threat: Most household spiders are harmless, but some can bite. Web building can be a nuisance.

Food: Insects like flies, mosquitoes, moths, crickets.

Prevention: Reduce clutter, vacuum regularly, install screens on windows.

4. Silverfish

Appearance: Tiny gray/silver wingless bugs with elongated flattened bodies, up to 1/2 inch long.

Threat: They damage books, photos, paper, fabrics, cardboard, and eat holes in them.

Food: Starch in book bindings, paper, photos, sugar, spices, cotton, linen, dead insects.

Prevention: Reduce humidity, eliminate food sources, use dehumidifiers, diatomaceous earth.

5. Centipedes

Appearance: Flattened brown/yellow segments with 15+ pairs of legs. Up to 6 inches long.

Threat: They can bite but aren’t dangerous. More of a nuisance.

Food: Small insects, worms, spiders.

Prevention: Reduce clutter and moist environments.

6. Millipedes

Appearance: Cylindrical brown bugs with many legs, up to 1-2 inches long.

Threat: Some species secrete a foul odor/liquid when threatened. Generally harmless.

Food: Decaying plant matter and fungi.

Prevention: Eliminate moist environments, reduce clutter, fix leaks.

7. Earwigs

Appearance: 1/2 – 1 inch long, reddish-brown, with signature pincers on their rear.

Threat: The pincers can give a pinch but are not dangerous.

Food: Plant matter and small insects.

Prevention: Remove debris/mulch outside, use insecticides, diatomaceous earth.

8. Fleas

Appearance: Tiny (1/16 inch long) wingless brown insects.

Threat: Flea bites are itchy and annoying, and they can transmit disease to pets & humans.

Food: Blood from pets, rodents, humans.

Prevention: Treat pets, vacuum often, clean bedding at high heat, use sprays.

9. Crickets

Appearance: Black field crickets are solid black. House crickets are yellowish-brown. ~1 inch long.

Threat: Just a nuisance from chirping. Eat fabric, paper, old boxes.

Food: Young plants, seeds, fruits, fungi, cloth, cardboard, dead insects.

Prevention: Seal cracks, remove food sources, use sticky traps.

10. Springtails

Appearance: Tiny (~1/16 inch) insects varying in color from white to gray to black. Have a tail-like appendage that allows them to jump.

Threat: Mainly a nuisance. Large numbers can damage plant roots and seedlings.

Food: Fungi, mold, decaying plant matter.

Prevention: Reduce moisture levels, allow ventilation, replace rotting wood.

11. Fruit Flies

Appearance: Tiny flies ~1/8 inch long. Red eyes, yellow-brown bodies.

Threat: Just an annoyance as they swarm food sources.

Food: Ripening/rotting fruit and vegetables. Standing water for breeding.

Prevention: Clean spills quickly. Remove ripe produce. Cover trash cans. Drain standing water.

12. Fungus Gnats

Appearance: Tiny dark flies with long legs and thread-like antennae. About 1/8 inch long.

Threat: Mostly harmless but large numbers are annoying. Larvae damage plant roots.

Food: Fungi, moldy surfaces, plant roots.

Prevention: Remove damp decaying matter, allow air circulation to dry out mold. Use sticky traps.

13. Boxelder Bugs

Appearance: 1/2 inch long black insects with red markings, an elongated oval shape, and 6 legs.

Threat: Just a nuisance as they enter homes in large numbers in fall seeking warmth. Give off odor when crushed.

Food: Boxelder trees, maple trees.

Prevention: Seal cracks, install door sweeps, use insecticides.

14. Stink Bugs

Appearance: 5/8 inch shield-shaped bugs in various colors like brown, green, gray.

Threat: Release a foul stench when disturbed or crushed. Otherwise harmless.

Food: Fruits, vegetables, nuts, berries, fruit trees.

Prevention: Seal cracks, clean up fallen fruits/berries, use insecticides.

15. Lady Bugs

Appearance: Small round beetles under 1/4 inch. Vary in color from red to orange to pink with black spots.

Threat: Harmless but a nuisance when they swarm indoors.

Food: Aphids and other garden pests.

Prevention: Seal cracks, install screens, vacuum up bugs.

16. Carpet Beetles

Appearance: Round oval insects around 1/16 – 1/8 inch long with black, white, brown, yellow, or orange markings.

Threat: Larvae eat and damage materials like wool, silk, leather, fur, and feathers.

Food: Protein-based materials, dead insects, animal hair/feathers.

Prevention: Clean thoroughly, wash bedding at high heat, store susceptible items in airtight containers.

17. Drugstore Beetles

Appearance: Tiny brown beetles about 1/8 inch long with lines/ridges on wings. Larvae are creamy white grubs.

Threat: They bore into containers to eat dried foods, herbs, spices, cereals, pasta, tobacco, drugs.

Food: Stored grain-based food products.

Prevention: Discard infested packages, store food in airtight containers, use pantry pest traps.

18. Mealworms

Appearance: Worm-like larvae up to 1 inch long that turn into dark brown beetles.

Threat: Eat stored grains and cereals. Mostly harm food products.

Food: Flour, cereals, meal, grain, seeds, dried pet food.

Prevention: Discard infested foods, clean shelves, store items in plastic/glass containers.

19. Pantry Moths

Appearance: Grayish moths about 1/2 inch long. Caterpillars are white/tan with dark heads.

Threat: Larvae contaminate food by leaving behind silk webbing and droppings.

Food: Grains, cereals, flour, nuts, seeds, chocolate, spices.

Prevention: Discard infested foods, clean pantry, store food in airtight containers.

20. Termites

Appearance: Small pale insects with straight antennae and thick waists. Workers are up to 1/4 inch.

Threat: They tunnel into and severely damage wood structures.

Food: Cellulose material – wood, paper products, fabric.

Prevention: Eliminate moisture. Have professional treatment. Replace damaged beams.

21. Booklice

Appearance: Tiny white/gray bugs under 1/16 inch long with long antennae.

Threat: Damage books, wallpaper, old boxes, and other starchy items by grazing on mold and fungi.

Food: Mold, fungal growths, starchy materials.

Prevention: Reduce humidity, clean off mold with fungicide, ventilate.

22. Drain Flies

Appearance: Delicate light gray flies less than 1/4 inch long with long legs and antennae.

Threat: Just an annoyance from swarming adults. Larvae in drains don’t directly harm humans.

Food: Algae, bacteria, fungi in moist organic buildup inside drains or septic systems.

Prevention: Clean drains, pour boiling water, try enzyme cleaners, bleach, traps.

How to Get Rid of Basement Bugs

Preventing and eliminating existing basement bugs requires diligence and pest-proofing your space. Here are the top ways to kick bugs out of the basement:

• Install weather stripping around doors and windows and seal cracks in the foundation. Caulk around pipes and utility openings.

• Remove all clutter like stacks of cardboard boxes, papers, and debris that offer hiding spots.

• Clean thoroughly by vacuuming, mopping, and sanitizing the basement. Throw away trash and recycling regularly.

• Store food in airtight plastic or glass containers. Never leave pet food dishes out.

• Fix any water leaks and moisture problems. Consider adding a dehumidifier.

• Improve ventilation by adding fans, vents, windows, or exhaust systems.

• Drain any standing water and fix leaky pipes or appliances.

• Fill small holes with steel wool, copper mesh, or caulk. Use door sweeps on entry doors.

• Limit pest access from outdoors by trimming plants/shrubs near the foundation. Move woodpiles farther away.

• Set out traps and monitor for signs of bugs. Use pesticides/insecticides if needed for serious infestations.

With diligence, you can eliminate existing pests and keep new ones out of your basement for good. Don’t give bugs any openings, food, water, or shelter, and your basement can stay creepy crawly free.