American cockroach vs Oriental cockroach
These two are easy to mix up. Here's how to tell an American cockroach from an Oriental cockroach, and whether either one bites or stings.
American cockroach
Periplaneta americana
Oriental cockroach
Blatta orientalis
≠The key differences
Larger (up to 30-40 mm), reddish brown with a pale margin behind the head and fully developed wings; better climber and more likely in kitchens and upper floors.
⚖︎Side by side
| American cockroach | Oriental cockroach | |
|---|---|---|
| To humans | Allergen carrier | Contaminant |
| Size | 30-50 mm body length | Males about 18-25 mm; females about 25-32 mm (body length) |
| Colours | Reddish brown, Dark brown, Pale yellow (pronotum margin) | Dark brown, Black, Reddish brown (young nymphs) |
| Family | Blattidae | Blattidae |
| Habitat | Warm, humid places in and around human structures: basements, boiler rooms, sewers, drains, crawl spaces, commercial kitchens and garbage areas. | Cool, damp and shaded areas around human buildings: basements, crawlspaces, drains, sewers, leaf litter and compost piles. |
| Range | Originally tropical; now cosmopolitan in warm buildings and sewer systems worldwide, common in temperate regions where it occupies heated structures. | Originally from the Middle East or Mediterranean region; now widespread worldwide in temperate to subtropical regions and commonly established in cities globally. |
| Active | Nocturnal; active year-round indoors and in sewers, most visible at night. | Mostly nocturnal; active year-round in warm buildings, outdoors in temperate climates mainly spring to autumn. |
| Pest? | Yes | Yes |
🔍How to spot an American cockroach
- Large reddish-brown body 30-50 mm long with fully developed wings in adults.
- Pronotum with a pale yellowish margin often visible as a ring around the shield behind the head.
- Smooth, shiny body with long antennae and spiny legs adapted for rapid running.
- Adults may fly short distances when disturbed (especially males).
🔍How to spot an Oriental cockroach
- Uniform dark brown to black, glossy, oval body about 18-32 mm long.
- Relatively slow-moving and poor climber; often found at ground level or in drains.
- Males smaller with short wings covering most of abdomen; females larger and broader with only tiny wing pads and no flight.
- Found in cool, damp locations such as basements, crawlspaces, leaf litter, compost and sewers.
?Frequently asked questions
What is the difference between an American cockroach and an Oriental cockroach?
Larger (up to 30-40 mm), reddish brown with a pale margin behind the head and fully developed wings; better climber and more likely in kitchens and upper floors.
Is an American cockroach or an Oriental cockroach more dangerous?
American cockroach: Allergen carrier. Oriental cockroach: Contaminant. American cockroaches are not venomous and do not inject toxins, but they contaminate food and surfaces with bacteria and can trigger allergic reactions and asthma in sensitized people. Oriental cockroaches do not bite or sting and are not venomous.
Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.