Pavement ant vs Odorous house ant

These two are easy to mix up. Here's how to tell a pavement ant from an odorous house ant, and whether either one bites or stings.

≠The key differences

Pavement ants have a visibly sculptured head and thorax and a two-segmented petiole that is apparent in profile; they do not emit the coconut odour.

	Pavement ant	Odorous house ant
To humans	Non-toxic	Non-toxic
Size	Workers 2.5-4 mm; queens 6-8 mm	Workers 2.4-3.3 mm long; queens larger (about 4-5 mm)
Colours	Brown, Dark brown, Black	Light brown, Dark brown, Black
Family	Formicidae	Formicidae
Habitat	Urban and suburban areas: cracks in pavement and sidewalks, under stones, curbs, building foundations, lawns and occasionally inside buildings.	Urban and suburban areas, inside buildings (kitchens, wall voids), under stones, wood, mulch and in soil; tolerant of varied habitats
Range	Native to Europe and parts of Asia; introduced and common across North America and other temperate regions worldwide.	Native to North America and widespread across the United States and southern Canada; found in diverse habitats from forests to cities
Active	Spring through fall (most active during warm months); workers forage day and night depending on temperature.	Active year-round in heated buildings; outdoors mostly spring to fall and during warm parts of the day
Pest?	Yes	Yes

Small workers 2.5-4 mm, uniformly brown to dark brown with a slightly darker gaster.
Two petiole nodes (two-segmented waist) and two short spines on the rear of the mesosoma.
Head and thorax show fine parallel sculpturing; antennae with 12 segments and a 3-segmented club.
Nests in cracks in pavement, along foundations and under stones; look for worker trails at nest entrances.

Very small workers (2.4-3.3 mm) with a smooth profile because the petiole is hidden by the gaster
Colour variable from light brown to dark brown or black
When crushed, workers give off a distinctive odour often described as rotten coconut, pine, or moldy cheese
Do not have a distinct antenna club and have 12-segmented antennae

Pavement ants have a visibly sculptured head and thorax and a two-segmented petiole that is apparent in profile; they do not emit the coconut odour.

Pavement ant: Non-toxic. Odorous house ant: Non-toxic. Pavement ants do not have dangerous venom. Odorous house ants do not have a sting.

Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.