Types of Cockroaches in California (and How to Tell Them Apart)

California is home to several cockroach species, but the ones you actually run into in a home or yard come down to a short list — and in Fresno and the Central Valley, the lineup is shifting as the Turkestan cockroach spreads. This guide covers the common types of cockroaches in California: how to identify each one, where it lives, whether it flies, and which roach is the one that really infests homes here.

The cockroaches Californians actually encounter range from the small indoor German cockroach to the large American “palmetto bug.”

The California cockroach comparison table

Use this table to narrow down what you are looking at. Size, color, where it lives, and whether it can fly are usually enough to identify the roach — and to tell a harmless outdoor wanderer from the German cockroach that actually breeds indoors.

German cockroach — the one that infests homes

If you see small, tan roaches in a Fresno kitchen or bathroom, they are almost certainly German cockroaches — about half an inch long with two dark stripes running behind the head. They are the only common California roach that truly breeds indoors, they multiply fast, and they are the hardest to get rid of. They also rarely fly. Read our full German cockroach guide →

A German cockroach — note the two dark parallel stripes just behind the head.

American cockroach — the big “palmetto bug”

The American cockroach is the largest common house roach — up to two inches, reddish-brown, with a pale yellow figure-8 marking behind the head. Despite the name it is not native; it lives in sewers, drains, and damp basements, can glide short distances, and is the roach people call a “palmetto bug” or “water bug.” See the American cockroach guide → or learn whether a palmetto bug is really a cockroach →

An American cockroach beside the yellowish figure-8 marking that helps identify it.

Oriental cockroach — the shiny black “water bug”

Oriental cockroaches are shiny, dark brown to nearly black, about an inch long, and neither sex really flies. They like cool, damp places — drains, crawlspaces, garages, and water boxes — and give off a strong musty odor. In California they are increasingly being replaced by the Turkestan cockroach. Read the Oriental cockroach guide →

An Oriental cockroach — dark, glossy, and flightless, found in damp, cool areas.

Turkestan cockroach — the roach taking over here

The Turkestan cockroach is an outdoor roach spreading rapidly across California, and according to UC IPM it is displacing the Oriental cockroach — especially in southern California and the Central Valley. Males are reddish-tan with cream-colored wing edges and fly to lights; females are darker. They live in water-meter boxes, irrigation valve boxes, and leaf litter. See why the Turkestan cockroach is taking over →

A male Turkestan cockroach, reddish-tan with cream wing margins — now common in Central Valley utility boxes.

Brown-banded cockroach

Brown-banded cockroaches are small, like German cockroaches, but they prefer warm, dry, high places rather than damp ones — upper walls, ceilings, behind picture frames, and inside electronics. You can spot two lighter bands across the wings and abdomen. They are less common in the Valley than the German cockroach but turn up in the same kinds of buildings.

Field cockroach — the German look-alike from outdoors

Field cockroaches look almost exactly like German cockroaches — small and tan with two dark stripes — but they have a telltale black stripe between the eyes and they live outdoors in mulch, leaf litter, and gardens. They wander into Central Valley homes in hot, dry weather looking for moisture, but they do not infest. Telling them apart matters, because one needs treatment and the other does not. How to tell a field cockroach from a German cockroach →

A field cockroach — nearly identical to a German cockroach, but note the dark stripe across the face between the eyes.

Less common cockroaches in California

A few other roaches turn up rarely. The three-lined cockroach is a small outdoor species spreading in irrigated landscapes; the smokybrown cockroach is a strong-flying mahogany roach that is now uncommon in California; and the Australian cockroach mostly appears in greenhouses and animal-rearing facilities. None of these are typical Fresno household pests. For corroborating identification, the UC IPM cockroach guide is the standard California reference.

“Which cockroach do I have?” — a quick guide

Small tan roaches in the kitchen or bathroom, with two stripes behind the head? German cockroaches — the one species that truly infests indoors. Act quickly.

A large reddish-brown roach near a drain or in the garage? Almost certainly an American cockroach — the “palmetto bug.”

A shiny near-black roach in a damp, cool spot? An Oriental cockroach — or, increasingly in the Valley, a Turkestan cockroach outdoors.

A small tan roach outdoors, or one that wandered in during a heat wave? Likely a field cockroach — check for the black stripe between the eyes.

Small roaches up high — on walls, ceilings, or in electronics? Brown-banded cockroaches, which prefer warm and dry over damp.

When cockroach identification matters

Identification matters most because it separates the German cockroach — which breeds indoors and needs prompt, thorough treatment — from outdoor roaches that mostly need exclusion and moisture control. It also tells you whether you are fighting an active indoor infestation or just the occasional invader coming in from the yard. Either way, our guide to getting rid of cockroaches in Fresno covers the treatment side, and you can match the roach in your own home here.

See our cockroach control →

Cockroach identification FAQ