How to identify it
Also called brown rat, sewer rat. Work down these in order — the first one is usually enough on its own.
- Tail shorter than head and body — the reliable separator from roof rats
- Heavy stocky build, blunt nose, small ears relative to head
- Droppings about three-quarters of an inch with blunt ends
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
- Burrows along foundations, under sheds, decks and concrete slabs
- Crawlspaces and basements
- Sewers and storm drains
- Ground-floor rooms, entering at or below grade
Signs it is already there
You will nearly always see the evidence before you see the pest itself.
- Burrow openings two to four inches across near foundations or under structures
- Large blunt-ended droppings
- Gnaw damage at ground level, including on plastic and soft metal
- Well-worn runways through vegetation
High. Costly or fast-moving if it is left alone.
Why it is harder to deal with than it looks
Burrow systems are extensive and often extend under hard surfaces where they cannot be reached. They are neophobic — wary of new objects — so traps frequently sit untouched for days before anything happens.
What actually works
Exclusion at and below grade: seal gaps around utility penetrations, crawlspace vents and door sweeps, and consider a rodent barrier where burrowing is established. Remove harbourage — woodpiles, dense ground cover, clutter against the structure. Trapping needs patience and correct placement along runways.
Common questions
How do I tell a norway rat from a roof rat?
Roof rats are slimmer, have a tail longer than the body, larger ears, and live high rather than low.
How do I tell a norway rat from a house mouse?
Size alone separates them; a Norway rat is several times the bulk of a mouse.
Where are norway rat usually found in a home?s
Burrows along foundations, under sheds, decks and concrete slabs Crawlspaces and basements Sewers and storm drains.
Is a norway rat dangerous?
Contaminate food and surfaces, gnaw structural material and wiring, and can undermine slabs and paving with burrowing. The usual health considerations around droppings apply.
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.