Pest Control
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There are around 50 species of ant in the UK, but only a handful are ones you are likely to notice, and fewer still come indoors. Knowing which one you have tells you where it nests, whether it stings, and what will and will not work against it.
Black garden ant
What it looks like: workers 3 to 5mm long, glossy black or very dark brown. Queens are up to about 15mm.
Where it nests: in soil, under paving slabs and stones, in lawns and at the base of walls. Signs are fine piles of soil between slabs and along path edges.
When you see it: workers are active from around March to October. Winged queens and males swarm on warm, humid days in mid-summer, usually July and August.
Indoors? Yes. This is the species that trails into kitchens looking for sugar. It does not sting. Our guide to black ants in the house covers what to do.
Yellow meadow ant
What it looks like: small, about 2 to 4mm, and yellow to yellowish-brown.
Where it nests: underground in grassland, gardens and lawns that are not cut very often. These are the ants that build the dome-shaped ant hills of fine soil, which can grow large and grassed-over if left undisturbed for years.
When you see it: it spends almost all its life underground, feeding largely on the honeydew of aphids on grass roots, so you mostly see the mounds rather than the ants.
Indoors? Rarely. It does not sting. Ant hills on a lawn are mostly a nuisance for mowing, and many people simply level them in autumn.
Red ants
What it looks like: reddish-brown, around 4 to 6mm. Several closely related species share the name, the most common being Myrmica rubra.
Where it nests: in damp soil, under stones and logs, and in lawns and borders.
Indoors? Occasionally. Unlike black garden ants, red ants can sting, and the sting is sharp. They are sometimes called fire ants, but they are not the tropical fire ants of other countries. If you have red ants nesting where children play, it is worth dealing with.
Red wood ant
What it looks like: large for a UK ant, with a red-brown head and thorax and a dark abdomen.
Where it nests: in woodland, especially conifer and mixed woods, in large mounds built from pine needles and twigs. Gardens that back onto woodland sometimes see them foraging.
Indoors? Almost never. They do not sting, but they bite and spray formic acid if their mound is disturbed. Wood ants are an important part of woodland ecology and are best left alone.
Brown ants and the invasive garden ant
Some ants that look like slightly paler black garden ants are something else. The one to know about is the invasive garden ant, a non-native species that forms very large colonies with many queens and has a habit of gathering in electrical fittings. It is hard to tell from the black garden ant by eye. Our guide to brown ants explains what to look for.
Tropical ants in heated buildings
Pharaoh ants and ghost ants are tiny, pale species that cannot live outdoors in the UK and survive only in heated buildings. They are more often found in hospitals, flats and commercial premises than in houses. Their colonies have many queens and can split when disturbed, so they should be identified before anyone treats them.
Why identification matters
Different ants nest in different places, form colonies of different sizes and respond to different baits. A treatment that works well on black garden ants can fail on an invasive or tropical species, and some home treatments make multi-queen colonies spread. If you are not sure what you have, a clear close-up photo is a good start.
When to call us
Call us if ants keep coming indoors, if you think you have red ants where people sit or play, or if the ants are very small and pale or gathering around sockets and switches. We identify the species, find the nest and treat it in the way that suits that ant. See our ant control page, or send us a photo.