🪳 Cockroaches

American cockroach

Periplaneta americana

The big reddish one. Lives in drains and sewers, comes indoors through a gap.

Size
One and a half to two inches (35–50 mm) — the largest common house roach
Colour
Reddish-brown, glossy
Risk
Moderate
When
Year round outdoors, with indoor sightings rising in summer heat and after heavy rain
An American cockroach from above: a large glossy reddish-brown roach with wings over its abdomen, very long antennae, and a pale yellowish marking on the shield behind the head.
The pale marking on the shield is the quickest separator from a German or Oriental cockroach. AI-generated illustration · FreePestControlInspection.com

How to identify it

Also called palmetto bug, water bug. Work down these in order — the first one is usually enough on its own.

  • A pale yellowish figure-of-eight marking on the shield behind the head
  • Fully developed wings; adults can and do fly, especially in heat
  • Long antennae, often as long as the body

What it gets mistaken for

Most people arrive at a pest name by ruling things out. These are the ones that genuinely look similar, and the detail that separates them.

Where you will find it

  • Sewers, drains, grease traps and storm drains
  • Crawlspaces, basements and utility rooms
  • Bathrooms at night, having come up a drain line
  • Mulch beds and around water meters outdoors

Signs it is already there

You will nearly always see the evidence before you see the pest itself.

  • Occasional large roaches at night, often in a bathroom or kitchen
  • Droppings with blunt ends and ridged sides, larger than a mouse dropping
  • Activity that spikes after heavy rain, when drains flood

Moderate. Worth dealing with, but not an emergency.

Why it is harder to deal with than it looks

Killing the one you see achieves nothing, because it did not come from an indoor population. The question is always how it got in. In older North Texas housing the usual answer is a failed cast-iron drain line or an unsealed plumbing penetration, and no amount of spraying closes that.

What actually works

Find and close the route. Check under-sink plumbing chases, floor drains, the gap around pipes entering walls, and any disused drain. Keep floor drains filled or capped. If several appear indoors regularly, a camera inspection of the drain line is often what actually solves it.

Common questions

How do I tell a american cockroach from a german cockroach?

The German is far smaller with two dark stripes, and indicates an indoor breeding population rather than an entry point.

How do I tell a american cockroach from a oriental cockroach?

The Oriental is smaller, much darker and duller, and the female has only stubby wing pads.

Where are american cockroach usually found in a home?s

Sewers, drains, grease traps and storm drains Crawlspaces, basements and utility rooms Bathrooms at night, having come up a drain line.

Is a american cockroach dangerous?

They travel through sewers before entering living space, so they carry contamination onto surfaces. Structurally harmless.

Identification guidance only. Under Texas law, applying pest control treatments for hire requires a licence from the Texas Department of Agriculture. This page describes what a pest looks like — it is not a diagnosis of your property or a treatment recommendation for it.