How to Get Rid of Roaches

The fastest reliable way to get rid of roaches is to bait them, not spray them: place small dots of cockroach gel bait in cracks where they hide, add an insect growth regulator, remove food and water, and check progress with sticky traps. Expect a light German cockroach infestation to collapse in 2-4 weeks and a heavy one in 6-8 weeks or more.

Before you start, figure out which roach you have, because the plan for small kitchen roaches is different from the plan for big ones coming up the drain.

Step 0: Identify the roach

• Small (1/2 inch), tan, in kitchen/bathroom, many sightings: German cockroach. Follow the full plan below.
• Small, banded, in bedrooms/electronics: brown-banded. Same plan, but spread bait through the whole house.
• Big (1-2 inches), occasional, near drains, basement, garage: American or oriental. Skip to "Big roaches" below.

Not sure? See types of cockroaches.

Step 1: Measure the problem

Place 6-10 sticky traps overnight: under the sink, behind the fridge and stove, beside the dishwasher, in the bathroom vanity, and in the pantry. Count roaches in the morning and note where most were caught. Those are your bait zones, and this count is your baseline. See cockroach traps.

Step 2: Clean and remove water

Roaches eat bait more readily when there's less competing food.

• Degrease the stovetop, range hood, the floor under and behind appliances, and the inside of cabinet doors.
• Vacuum droppings, egg cases, and visible roaches (empty the vacuum outside).
• Store food, including pet food, in sealed plastic or glass containers. Don't leave pet food out overnight.
• Take trash out nightly; use a lidded can.
• Fix dripping faucets and leaking P-traps, dry the sink cabinet, don't leave wet sponges or dish rags out.
• Cut clutter: cardboard boxes and paper bags are prime roach harborage.

Don't clean the bait spots with strong cleaners once bait is in place.

Step 3: Bait - the best cockroach killer for German roaches

Gel bait is a slow-acting insecticide in a food matrix. Roaches eat it, return to their hiding spot, and die there; other roaches then eat their droppings and bodies and die too. That secondary kill is what reaches roaches you never see.

• Apply small dots (about the size of a pea or smaller) in cracks, crevices, and corners near where roaches hide - not out in the open. Hinges, behind the sink, where pipes enter walls, along the back edges of cabinets, under the stove and fridge.
• More placements, smaller amounts: 20-40 small dots spread out beat a few large blobs.
• Recheck every 3-5 days, add bait where it's been eaten.
• Keep sprays away from bait. Insecticide spray residue makes roaches avoid it.
• Rotate actives if roaches ignore the bait after a few weeks: switch between products based on indoxacarb, fipronil, abamectin, dinotefuran, or hydramethylnon.

Enclosed bait stations work too and are better where kids or pets can reach. Details and product types: cockroach gel bait.

Step 4: Add an IGR

An insect growth regulator (hydroprene or pyriproxyfen) doesn't kill quickly, but it stops nymphs from becoming fertile adults. Use point-source discs in cabinets or an aerosol IGR in cracks (not on the bait). It shortens the time to elimination and helps in apartments where new roaches keep arriving.

Step 5: Dust wall voids with boric acid

A very light dusting of boric acid (a fine, barely visible film) behind outlet and switch plates on kitchen walls, under appliances, and in the void under the sink kills roaches for months if it stays dry. Heavy piles don't work - roaches walk around them. Keep it away from food, kids, and pets. See boric acid and diatomaceous earth.

Step 6: Seal

Caulk gaps around pipes under sinks and behind toilets, cracks along baseboards and backsplashes, and gaps between cabinets and walls. Install door sweeps and screen vents. In apartments this slows roaches coming from neighbors.

Step 7: Monitor and follow up

Re-set sticky traps weekly in the same spots. Numbers should drop sharply within 2-3 weeks. Keep baiting until you catch zero roaches for 3-4 weeks in a row; egg cases can hatch weeks after the adults are gone.

Big roaches: American, oriental, smokybrown

For large roaches that come in from outside, the plan is exclusion plus outdoor control:

1. Run water in unused drains weekly, use drain covers, and seal gaps around pipes.
2. Add door sweeps, fix weatherstripping, and screen crawl space vents and weep holes.
3. Reduce moisture in basements and crawl spaces.
4. Move mulch, firewood, and leaf litter back from the foundation; clean gutters.
5. Use granular bait around the foundation and bait stations in garages and basements.
6. Apply a residual perimeter insecticide labeled for cockroaches around the foundation and entry points (follow the label exactly).

What doesn't work (and why)

• Bug bombs/foggers: the mist doesn't reach roaches inside walls and appliances, scatters them, and leaves residue that repels them from bait. They're also a fire and exposure hazard.
• Spraying what you see: kills a few, leaves the colony and egg cases.
• Bleach: kills only roaches it soaks; no residual effect, no effect on eggs.
• Baking soda, bay leaves, essential oils, and "what smell do roaches hate" remedies: little or no evidence; repellents just move roaches around.
• Ultrasonic repellers: tested repeatedly with no meaningful effect.
• Over-the-counter bait used in a sprayed kitchen: contaminated bait is ignored.

How to kill a single cockroach

Stepping on it or a flyswatter works; for a big roach, a spray of soapy water or a quick vacuum is less messy. Wipe the spot afterward. A single big roach in summer is often a visitor; a single small tan roach indoors is a reason to put out traps.

Safety

Always read and follow the label - it's the law under EPA pesticide rules. Keep baits and dusts out of reach of children and pets, prefer enclosed stations in their reach, and never apply sprays on food-prep surfaces. Call Poison Control (1-800-222-1222) for accidental exposure.

When to call a pro

Call a licensed exterminator if you're in an apartment or condo building, if counts aren't dropping after 4-6 weeks of proper baiting, if roaches are in electronics or the whole house, or if anyone in the home has asthma. Initial German cockroach service usually costs roughly $150-$400 with follow-ups (approximate). See cockroach extermination.