Bug Identifier
Comparison

Odorous House Ant vs Argentine Ant

By the Bug Identifier Editorial Team. Updated September 27, 2026. 3 minute read.

Odorous House Ants and Argentine ants are easy to mix up at a glance, but a few details separate them quickly. Here is how to tell which one you found and what, if anything, you should do about it.

Quick answer

Check for this first. An odorous house ant has small, uniformly dark ant with an uneven thorax, while an Argentine ant has uniform light-brown body with one flat node.

Side-by-side comparison

Odorous House AntArgentine Ant
GroupAntsAnts
Scientific nameTapinoma sessileLinepithema humile
Size2–3 mm2–3 mm
ColorsBlack and BrownBrown
Legs6 legs6 legs
WingsNoNo
Bites or stingsNoNo
RiskNuisanceNuisance
Key featureSmall, uniformly dark ant with an uneven thoraxUniform light-brown body with one flat node

Key differences

  • Color: Odorous House Ants are black and brown; Argentine ants are brown.
  • Where found: look for odorous house ants in the kitchen and in the bathroom; Argentine ants turn up in the kitchen and in gardens and on plants.
  • Signature feature: Odorous House Ants: small, uniformly dark ant with an uneven thorax. Argentine Ants: uniform light-brown body with one flat node.

How to identify odorous house ants

A small, dark brown to black ant that trails along counters and sinks looking for sweets. Crushed workers give off a smell often compared to rotten coconut.

  • Small, uniformly dark ant with an uneven thorax
  • Rotten-coconut odor when crushed
  • Erratic, fast-moving trails, especially after rain

See the odorous house ant profile

How to identify Argentine ants

A small, light-to-dark brown ant that forms huge, cooperating supercolonies. Wide, busy trails often stream into kitchens during hot or rainy weather.

  • Uniform light-brown body with one flat node
  • Very wide, steady trails several ants across
  • Musty, greasy odor when crushed

See the Argentine ant profile

Which one is more dangerous?

Neither is more dangerous than the other; both are rated nuisance on our scale.

Odorous house ants are a nuisance only; they rarely bite and don't sting. Argentine ants don't sting and rarely bite; they protect aphids and scale insects on garden plants.

Where and when you'll see each

Odorous House Ants turn up in the kitchen and in the bathroom, mostly in spring and summer. Argentine Ants turn up in the kitchen and in gardens and on plants, mostly in spring, summer and fall.

Because they share habitat, you may find both in the same place, so check each individual.

What to do if you find one

Odorous House Ants: Wipe up crumbs and sugary spills and rinse recyclables. Read the full removal guide for more.

Argentine Ants: Apply sugar-water baits outdoors along trails. Read the full removal guide for more.

Biology: ants

Ants live in colonies ruled by one or more egg-laying queens. The workers you see are sterile females foraging for the rest of the colony, so killing visible ants rarely solves anything. Winged ants, called swarmers, appear when a mature colony sends out new kings and queens.

Frequently asked questions

What is the main difference between odorous house ants and Argentine ants?

Color: Odorous House Ants are black and brown; Argentine ants are brown.

Which is bigger, an odorous house ant or an Argentine ant?

Odorous House Ant: 2–3 mm. Argentine Ant: 2–3 mm.

Do odorous house ants or Argentine ants bite?

Odorous House Ants do not bite. Argentine Ants do not bite.

Where are they usually found?

Odorous House Ants: in the kitchen and in the bathroom. Argentine Ants: in the kitchen and in gardens and on plants.