Earwigs, or "pincher bugs," show up under sinks, in the bathtub and in the laundry room, usually after a hot, dry spell or a cold snap. Most "how to get rid of earwigs" articles, including an earlier version of this one, repeat the same tip: boric acid kills them on contact. It doesn't. Here's how boric acid and borax actually work, what university entomologists recommend instead, and which homemade trap people report catching hundreds a night.
Indoors: vacuum them up, fix the dampness, and seal gaps around doors, windows and the foundation. UC IPM says indoor spraying won't stop earwigs coming in, and the ones inside die on their own because there's little for them to eat.
Outdoors: cut back mulch and moisture next to the house, then trap or bait. Boric acid works as an eaten bait, not a contact killer, and there are boric acid granular baits labeled for earwigs. UC IPM rates spinosad baits as the most effective, environmentally sound option. An oil-and-bait trap emptied daily can pull out hundreds.
Does Boric Acid Kill Earwigs?
Yes, but not the way most websites say. Search this question and you'll find nearly the same sentence on several big sites: boric acid "kills earwigs on contact." The National Pesticide Information Center describes how it really works. Boric acid kills insects "if they eat it," disrupting their stomach and possibly their nervous system, and it can also scratch their outer coating. That's a slow process, measured in days, which is why a line of powder across the floor rarely stops the earwig walking over it tonight.
Where boric acid does work is as a bait. Granular baits made with boric acid are registered and labeled for earwigs. For example, Niban Granular Bait (5% orthoboric acid, EPA Reg. No. 64405-2) lists European earwigs on its label, to be scattered around a building's perimeter and near entry points. One pest control technician on Reddit recommends pairing a boric acid bait with a perimeter spray. The bait is the part earwigs actually eat.
Owner reports reflect the difference. On Reddit, one homeowner says boric acid "has been working." Another tried boric acid powder and got "nothing," then wrote, "I didn't know there was the granular bait option."
What about borax?
Borax is a sodium salt of boric acid, so it belongs to the same family of boron compounds (NPIC). In bait form it can work the same way, as a slow stomach poison. But laundry borax isn't registered or labeled for insect control, so mixing it into homemade bait is off-label. A labeled boric acid bait is the safer, legal version of the same idea. Either way, keep boron products away from children and pets. NPIC notes young children are at higher risk because they crawl and put things in their mouths.
What Actually Works, Ranked by the Evidence
| Method | Where | What the evidence says |
|---|---|---|
| Fix moisture and mulch | Outdoors, at the foundation | Clemson and UC IPM both put this first. Earwigs need cool, damp shelter |
| Vacuum and seal | Indoors | UC IPM and Clemson: vacuum or hand-remove, then caulk and weatherstrip. Indoor earwigs die off on their own |
| Oil traps and rolled-newspaper traps | Garden, foundation beds | UC IPM: daily trapping cuts populations "to tolerable levels." Owners report hundreds a night |
| Spinosad bait | Outdoors, around plants and foundation | UC IPM's top-rated product. Less effective where other food is plentiful |
| Boric acid granular bait | Perimeter, entry points, under appliances | Labeled for earwigs. Works when eaten, over days |
| Boric acid powder on floors | Indoors | Slow, often ignored, and a hazard for kids and pets |
| Indoor bug spray | Indoors | UC IPM: won't prevent earwigs entering, not recommended |
The Trap That Catches Hundreds
UC IPM's recipe is simple: fill a low-sided can, like a tuna or cat food can, with vegetable oil and a drop of bacon grease or fish oil, and sink it so the rim is level with the soil. Earwigs come for the smell, fall in and can't climb out. Rolled newspaper, corrugated cardboard, bamboo tubes or a short piece of garden hose also work. Set them near plants or the foundation at dusk, and in the morning shake the earwigs out into a bucket of soapy water.
The popular Reddit version swaps in soy sauce for the bait: roughly equal parts soy sauce and vegetable or olive oil in a shallow dish. Results:
- "I've trapped hundreds in a week." (Michigan)
- "Catches hundreds in [a] night, several THOUSANDS have already been captured this year." (a permaculture gardener)
- One shed owner set four traps and caught one earwig in each, which is a reminder that traps work best right where earwigs are hiding.
Gardeners on YouTube report similar numbers. Under Next Level Gardening's earwig video (about 355,000 views), one viewer caught about 15 per bowl in a single night with olive oil and soy sauce, and another catches about 50 a night. A third says oil traps keep thousands of earwigs in check "a bit" but don't eliminate them. Indoors it can go the other way: under Utah State University Extension's trapping video, one viewer set three oil-and-tuna traps for an indoor infestation, watched earwigs walk around them at night, and caught none. Traps work best outside, where the earwigs live.
The key, per UC IPM, is to empty and reset them every day until catches drop off.
Why Earwigs Come Inside
Earwigs live outdoors under mulch, boards, rocks, woodpiles and leaf litter (Clemson). They come in when conditions outside turn "too dry, too hot, or too cold" (UC IPM), and they look for moisture. That's why they show up under sinks, in bathrooms, laundry rooms and garages. Clemson also notes they often ride in on potted plants brought indoors and gather around moisture problems near doors, windows and garages. Outdoor lights draw them too. UC IPM recommends switching white outdoor bulbs to yellow.
The Earwigs in Our Area
Clemson Extension lists three earwigs for South Carolina: the European earwig (the most common), the ring-legged earwig and the striped earwig, which is common in fields and gardens. All three are handled the same way.
Are Earwigs Harmful?
Not to people. UC IPM says earwigs generally don't attack humans, though they can pinch if trapped in clothing or sat on. The old story about earwigs crawling into ears is folklore. They don't spread disease, and UC IPM notes large numbers indoors "aren't a health hazard." Outdoors they're mixed: they chew seedlings, flowers and soft fruit, but they're also important predators of aphids. If your yard is mostly lawn, trees and shrubs, UC IPM says earwigs usually aren't worth treating at all.
Step-by-Step Plan
- Vacuum the ones inside and empty the bag or canister outdoors.
- Find the moisture. Fix leaks under sinks and around tubs, run a dehumidifier in damp basements, and redirect downspouts and sprinklers away from the foundation.
- Pull mulch and leaf litter back from the foundation, clear gutters, and move firewood, boards and pots off the wall.
- Seal entry points: door sweeps, weatherstripping, and caulk around windows, pipes and where the siding meets the foundation.
- Trap or bait outdoors with oil traps emptied daily, a spinosad bait, or a boric acid granular bait labeled for earwigs, following the label.
- Swap white porch bulbs for yellow ones.
When to Call a Professional
- Earwigs keep coming in after you've fixed moisture and sealed gaps
- Large numbers are coming from a crawl space or under a slab
- You'd rather not handle baits around children or pets
Our residential pest control service treats the perimeter and entry points where earwigs and other occasional invaders come in, across South Carolina, North Carolina and Virginia.
Key Takeaways
- Boric acid doesn't kill earwigs on contact. It's a stomach poison that works as an eaten bait, over days.
- Use a labeled bait (boric acid granules or spinosad), not loose powder or laundry borax.
- Oil traps emptied daily can catch hundreds. Soy sauce and oil is the popular homemade version.
- Indoors, vacuum and seal. Indoor spraying doesn't stop them coming in.
- Fix moisture and mulch at the foundation. That's where earwig problems start.
- They're harmless to people and eat aphids in the garden.
Sources: National Pesticide Information Center, Boric Acid General Fact Sheet; M. L. Flint, "Pest Notes: Earwigs", UC IPM Publication 74102; P. Zungoli and E. Benson, "Earwigs", Clemson Cooperative Extension HGIC, revised 2024; Nisus Corporation, Niban Granular Bait label, EPA Reg. No. 64405-2; Next Level Gardening, "How to Get Rid of Earwigs", YouTube; Utah State University Extension, "How to Trap Earwigs", YouTube; homeowner and technician accounts from Reddit (via Google search excerpts) and YouTube comments.
Frequently Asked Questions
Yes, but slowly and only when they eat it. Boric acid is a stomach poison, not a contact killer, despite what many websites say. It works best as a granular bait labeled for earwigs, scattered around the foundation and entry points, and takes days to work.
Borax is a sodium salt of boric acid and can act as a slow stomach poison if earwigs eat it, but laundry borax isn't registered or labeled for insect control. A boric acid granular bait labeled for earwigs is the safer, legal option. Keep any boron product away from children and pets.
Direct contact with soapy water, or vacuuming them up. Neither prevents more from coming in. For lasting control, fix moisture near the house, seal entry points, and trap or bait outdoors.
Vacuum the earwigs you see, fix leaks and damp areas, and seal gaps around doors, windows and the foundation. UC IPM notes indoor spraying won't stop earwigs from entering and that the ones inside eventually die because there is little for them to eat.
A shallow can of vegetable oil with a little bacon grease or fish oil, sunk level with the soil, as UC IPM recommends. Many gardeners use equal parts soy sauce and oil, and some report catching hundreds a night. Rolled newspaper or cardboard set out at dusk also works. Empty traps every morning.
Earwigs come indoors when it's too dry, too hot or too cold outside, looking for moisture. They often gather around leaky plumbing, damp basements, and moisture problems near doors, windows and garages, and can ride in on potted plants.
No. They can pinch if trapped in clothing or sat on, but they don't spread disease and aren't a health hazard indoors, according to UC IPM. In gardens they damage seedlings and soft fruit, but they also eat aphids.
Outdoors, earwigs are important predators of aphids, so in a yard of mostly lawn, trees and shrubs, UC IPM says they usually aren't worth treating. Control matters mainly in vegetable gardens and flower beds, and when they come indoors.
Moisture and shelter: mulch, leaf litter, boards and woodpiles against the foundation, leaky spigots and downspouts, and outdoor lights. UC IPM recommends yellow outdoor bulbs, which attract fewer earwigs.
Clemson Extension lists the European earwig as the most common species in South Carolina, along with the ring-legged earwig and the striped earwig, which is common in fields and gardens.
Photo credits: Charles J. Sharp, CC BY-SA 4.0; Janna Layton, CC BY-SA 4.0; Daniel Das, CC0; via Wikimedia Commons.