Skip to content

Is it a cockroach or a water bug?

The short answer

Almost always a cockroach. What matters is which one: a small tan roach with two dark stripes behind the head is a German cockroach, which breeds indoors and is a serious infestation. Large, dark roaches that wander in from outside, drains or basements are usually American or oriental cockroaches, and they are a much easier problem.

Why the species decides everything

German cockroaches complete their whole life cycle indoors, reproduce quickly, and hide in warm equipment — behind a fridge, inside a dishwasher, in the base of a kettle, in a motor housing. Treating them takes gel baiting and at least one follow-up visit timed to the egg hatch. Large outdoor species are typically entering from a drain, a sewer line, a crawl space or under a door, and the answer is mostly exclusion and moisture control.

What not to do before a professional treatment

Do not blanket-spray a kitchen with a repellent surface spray. It scatters German cockroaches deeper into wall voids and adjoining units, and it contaminates the surfaces where gel bait needs to be placed. It is one of the few cases where a cheap intervention measurably makes the professional job harder.

Seeing a German cockroach in daylight generally means the population is large enough that the harbourage is crowded. It is a scale signal, not a coincidence.

Also asked

Does seeing one cockroach mean there are hundreds?
For a large outdoor species wandering in, no — one really can be one. For a German cockroach, a single sighting means breeding is happening somewhere in the building, because that species does not live outdoors in most of North America.

Companies whose reviewers name cockroaches

803 pest control businesses in the United States and Canada have reviewers who write about cockroaches. Every listing shows the full rating distribution rather than the average, the share that is one or two star, and whether the owner replies.

Cockroaches

Read next

General information about pest problems and about hiring, not advice about your specific property. Pest control licensing, wildlife protection and landlord and tenant law are all set state by state and province by province across the United States and Canada, so your own regulator is the current answer. How we read the data.