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Be careful

German cockroach

Blattella germanica
Also called German roach, croton bug

German cockroaches do not bite, but their droppings and shed skins can set off allergies and asthma, and they can carry germs onto food and dishes.

German cockroach, photo 1
Photo: hhulsberg, CC0, via iNaturalist
Size13–16 mm (about 1/2 to 5/8 inch)
Where in the houseKitchen, bathroom, pantry
WhenYear-round, because they live entirely indoors; they are active mainly at night.

Check these features

  1. Light tan to light brown body
  2. Two dark, parallel stripes running lengthwise on the shield just behind the head
  3. Wings cover the body but adults do not fly
  4. Young (nymphs) are smaller and darker with a pale stripe down the middle of the back
  5. Females often carry a light tan egg case sticking out of the rear end

Bites and stings

Does not bite people. The health concern is allergens from droppings and shed skins, which can cause sneezing, congestion and asthma attacks, and germs carried onto food. Anyone whose asthma worsens at home should talk with a doctor.

What to do

  1. Catch or photograph one to confirm the two dark stripes behind the head, since German cockroaches need a different approach than the larger outdoor species.
  2. Put sticky traps along wall and floor edges, under the sink, and behind the stove and refrigerator, and check them for several days to see where activity is heaviest.
  3. Use bait stations or gel bait placed in cracks and hidden spots near where traps catch the most, following the product label; skip sprays and bug bombs, which tend to scatter them.
  4. Clean up crumbs and grease, wash dishes before bed, and vacuum hiding spots with a HEPA or multi-filter vacuum to remove droppings and shed skins that cause allergies.
  5. If the problem continues after a few weeks, or you live in an apartment building, contact a licensed pest professional and your landlord, since roaches move between units.

Look-alikes

Brown-banded cockroachSame size, but it has two pale bands across the wings and body instead of two dark stripes behind the head, and it hides high up and away from the kitchen.
American cockroachThree to four times longer, reddish brown, with a pale yellow rim around the shield behind the head instead of two dark stripes.
Oriental cockroachAbout twice as long, shiny black to very dark brown, with short or stubby wings, and usually found in damp basements and drains rather than kitchen cabinets.

Why it came inside

German cockroaches live only inside buildings and are not found living outdoors in the US; they arrive in grocery bags, boxes, used appliances and furniture, or move in through walls and pipes from neighboring apartments, then stay close to warmth, food and water.

Keep it out

  • Store food, pet food and cereal in sealed containers.
  • Fix dripping faucets and leaks, and do not leave dishes soaking overnight.
  • Caulk cracks and seal gaps around pipes and wires under sinks and behind appliances.
  • Check grocery boxes, used appliances and secondhand furniture before bringing them in.
  • Take out trash often and keep bins covered.

What helps

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Sticky traps

Flat glue traps set along walls and in corners show what is moving through and where. Place them where pets and children can't reach.

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Bait stations

Enclosed baits work slowly as insects carry the bait back to where they hide. Don't spray near the baits, and follow the label.

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Caulk and sealant

Silicone or siliconized acrylic caulk closes cracks around windows, pipes and baseboards. Bigger gaps need foam backer rod or expanding foam first.

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Airtight pantry containers

Glass or thick plastic containers with tight lids keep pantry pests out of flour, cereal, rice and pet food.

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Vacuum with a hose

Lets you remove bugs, webs and egg sacs without touching them. Empty the bag or canister outside right away.

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Sources

  1. University of California Statewide IPM Program (Pest Notes: Cockroaches)
  2. University of Kentucky Entomology (ENTFACT-614)
  3. U.S. Environmental Protection Agency (archived page, Cockroaches and Schools)
  4. Environmental Health Perspectives / NIEHS researchers (via NIH PubMed Central)
  5. Rutgers New Jersey Agricultural Experiment Station

Checked October 18, 2026. Rating backed by 4 sources. How we rate danger.