How to get rid of cockroaches: what works and when to call a pro

Why roaches matter

Cockroaches can carry germs that cause food poisoning and diarrhea, and their saliva, droppings and shed skins can set off allergies and asthma, especially in children (UMN Extension). EPA says roach allergens likely play a big role in asthma in cities (EPA).

Know which roach you have

• German cockroach. The most common indoor roach. Adults are about half an inch long, with two dark stripes behind the head. They’re found near plumbing in kitchens and bathrooms, in cupboard cracks and under sinks (UMN Extension).
• Oriental cockroach. Often called a “water bug,” it favors damp basements and drains (UMN Extension).
• Brown-banded and American cockroaches also infest homes (UMN Extension).

To see where they are, set sticky traps tight against walls, corners and the backs of cabinets (UMN Extension).

Steps that work

• Clean up. Store food in tightly sealed containers, don’t leave pet food out overnight, take trash out daily and fix leaky pipes. Vacuum floors, cracks and crevices, ideally with a HEPA filter, to remove roaches, egg cases and debris (UMN Extension).
• Clear clutter. Get rid of cardboard boxes, paper bags and stacks of newspapers where roaches hide (UMN Extension, EPA).
• Seal entry points. Caulk cracks and crevices, and plug gaps around pipes with steel wool (UMN Extension).
• Use baits. Baits act slowly, so results may not show right away. Put them where you see roaches, and keep any boric acid dust away from children and pets (UMN Extension).
• Spray only cracks. If you use a spray, apply it into cracks and crevices, not across open surfaces, and follow the label (UMN Extension, EPA).

EPA recommends integrated pest management: removing food, water and shelter first and using pesticides only as needed (EPA, EPA).

Why foggers waste money

NPIC says foggers may not work on pests that hide, like cockroaches (NPIC). In a study of infested apartments, foggers didn’t reduce German cockroach numbers, while gel baits costing about the same caused large declines. Fogging also left pesticide residues on kitchen surfaces far above the levels measured before treatment (NIH study). If you still use one, follow the label, use only one per room and stay out for the time on the label (EPA).

Renting or in a multi-unit building?

Roaches move between units, so University of Minnesota Extension says to treat the infested unit and the units around it (UMN Extension). Tell your landlord or building manager in writing and ask how the building handles pest control.

When to call a pro

University of Minnesota Extension says hiring a pest management service is often the best way to control a cockroach infestation (UMN Extension). Call one if roaches keep showing up after a few weeks of baiting and cleanup, or if you live in a building with many units.

• Get written quotes from more than one company, and ask what product they’ll use, where and how often.
• Ask whether follow-up visits are included.
• Check the company’s license with the Illinois Department of Public Health.
• Watch for door-to-door scams and high-pressure sales (FTC, Illinois Attorney General).

Other pests? See our mice guide, our bed bug guide and our pest control guide. Roaches can set off asthma; see our guide to asthma inhaler costs.