Household Insects: Identify the Bug and Find the Right Fix

You found a bug in the kitchen, the bed, the dog’s fur or a nest under the eaves, and you want to know two things: what is it, and what should you do? Start with where you saw it and what it looks like. The table below points you to the right guide. Getting the identification right first saves money, because treatments that work on one insect often do nothing for another.

Quick ID: which insect do you have?

Other common indoor insects. Spiders, silverfish, centipedes, crickets, stink bugs and lady beetles also turn up indoors. Most are occasional invaders that wander in from outside. They do not eat your food or damage the house, and a vacuum, sealing gaps and reducing moisture usually handle them.

Garden pests. If the trouble is on your plants or lawn, see the guides to aphids, spider mites and dandelions, listed below this article.

Indoor and outdoor insects

Household insects fall into a few rough groups, and the group tells you a lot about the fix.

• Insects that live and breed indoors. German cockroaches, pantry pests, carpet beetles, bed bugs and fleas complete their life cycle inside the home. Control means finding and removing the source, such as infested food, a pet bed or a mattress.
• Insects that nest outside and come in. Ants, most spiders, crickets, centipedes and many beetles nest outdoors and wander in through gaps. Sealing entry points and fixing moisture does more than spraying inside.
• Insects that attack the structure. Termites feed on wood in and under the house and need a different approach entirely.
• Stinging insects. Wasps and yellowjackets mostly matter when they nest near doors, play areas or inside walls.

Seasonal patterns

Insect problems follow the calendar, so the time of year is another useful clue.

• Spring: termite swarmers emerge indoors on warm days, often after rain. Carpet beetle adults show up on windowsills.
• Summer: wasp and yellowjacket colonies grow, and garden pests build up.
• Late summer and fall: yellowjackets scavenge food outdoors. Cooler autumn weather, long rains and drought all push outdoor insects toward buildings.
• Year-round indoors: German cockroaches, which do not live outdoors, along with pantry pests and bed bugs.

Our seasonal pest calendar has more detail.

Prevention overview

Most insects found inside a house came in from outdoors. Blocking their way in prevents many problems before they start:

1. Seal under doors. If you can see daylight under an exterior door, add a door sweep or threshold. Gaps as small as 1/16 inch let insects and spiders in.
2. Seal utility openings where pipes, wires, dryer vents and cables enter, using caulk, foam, or copper or steel mesh.
3. Caulk cracks around windows, doors and trim.
4. Repair torn screens and keep them on during the warm months.
5. Screen vents in the attic, roof and crawlspace.
6. Store food in sealed containers and clean up crumbs and spills.

If you use an exterior insecticide treatment, treat it as a supplement to sealing, not a replacement. The integrated pest management guide explains how to combine these steps.

How to get an insect identified

If the table does not settle it, get an expert opinion before you buy any product.

• Collect several specimens if you can, including different life stages (larvae and adults) or winged and wingless forms.
• Preserve them in a small, tightly sealed container of rubbing alcohol (70% isopropyl) or hand sanitizer.
• Pack them in a small box with padding. Envelopes, even padded ones, usually crush insects.
• Write down where and when you found them: which room, indoors or outdoors, and what they were on.
• Contact your county extension office. Many land-grant university extension programs identify insects, sometimes for a small fee. Services vary by state, so call first. A photo can help, but labs often need the actual specimen.

When to call a professional

Many insect problems are DIY jobs: pantry pests, carpet beetles, most ant trails, occasional invaders and garden pests. Call a licensed pest control company when:

• You suspect termites or bed bugs. Both need careful inspection and specialized treatment.
• German cockroaches keep coming back after you have cleaned up and baited.
• A wasp or yellowjacket nest is inside a wall, in the ground near a busy area, high up, or someone in the house is allergic to stings.
• You cannot find the source after a thorough search.

Our guide to choosing a pest control company explains what to ask before you hire.