What Are the Most Common Insects in the UK?
The United Kingdom is home to more than 27,000 described insect species, ranging from microscopic parasitoid wasps to the impressive stag beetle. While the full diversity is staggering, certain species are so abundant and widespread that almost everyone in Britain encounters them regularly. This guide introduces the insects you are most likely to see in gardens, parks, fields, and woodlands across the UK.
How Do We Define “Common”?
Commonness can be measured in different ways: total population size, geographic range, or frequency of human encounters. The species listed here score highly on all three measures—they are abundant in numbers, widespread across the UK, and frequently noticed by the general public.
Beetles (Coleoptera)
With over 4,000 species in the UK, beetles are the most species-rich insect order in Britain. Several are extremely common:
- Seven-spot ladybird (Coccinella septempunctata) – Britain's most recognisable beetle, found in gardens, hedgerows, and meadows. Both adults and larvae are voracious predators of aphids.
- Harlequin ladybird (Harmonia axyridis) – An invasive species that arrived in the UK in 2004 and has since become one of the most frequently encountered ladybirds. Highly variable in colour and pattern.
- Black clock beetle (Pterostichus madidus) – A common ground beetle found under stones, logs, and plant pots. Shiny black, approximately 15 mm long.
- Soldier beetles (Rhagonycha fulva) – The red soldier beetle (or “bloodsucker beetle”) is abundant on flower heads in summer, particularly hogweed and other umbellifers.
Flies (Diptera)
Flies are one of the most abundant insect orders in the UK, with over 7,000 species:
- Common housefly (Musca domestica) – Ubiquitous around human habitations.
- Bluebottle (Calliphora vomitoria) – The large, metallic blue fly commonly seen buzzing around bins and carrion.
- Crane flies (Tipula species) – “Daddy longlegs” are among the most conspicuous flies in autumn, when adults emerge in large numbers from lawns and grassland.
- Marmalade hoverfly (Episyrphus balteatus) – One of the most common hoverflies, with distinctive orange and black banding. A valuable pollinator and aphid predator.
| Species | Order | Size | Where You’ll See It |
|---|---|---|---|
| Black garden ant (Lasius niger) | Hymenoptera | 3–5 mm | Gardens, pavements, kitchens |
| Seven-spot ladybird (Coccinella septempunctata) | Coleoptera | 5–8 mm | Gardens, hedgerows, meadows |
| Common wasp (Vespula vulgaris) | Hymenoptera | 12–17 mm | Gardens, woodland, picnics |
| Crane fly (Tipula spp.) | Diptera | 15–25 mm | Lawns, grassland, around lights |
| Large white butterfly (Pieris brassicae) | Lepidoptera | 58–63 mm wingspan | Gardens, allotments, farmland |
| Common earwig (Forficula auricularia) | Dermaptera | 12–17 mm | Under pots, stones, bark |
| Green shield bug (Palomena prasina) | Hemiptera | 12–14 mm | Gardens, hedgerows, woodland edges |
Ants, Bees, and Wasps (Hymenoptera)
- Black garden ant (Lasius niger) – Almost certainly the most frequently encountered insect in the UK. Present in virtually every garden.
- Common wasp (Vespula vulgaris) – Abundant from spring to autumn, with colonies reaching peak size in August and September.
- Buff-tailed bumblebee (Bombus terrestris) – One of the first bumblebees to emerge in spring and one of the most common throughout the season. Queens can sometimes be seen flying on mild winter days.
- Honey bee (Apis mellifera) – While not native (it is managed by beekeepers), the honey bee is extremely common across all UK habitats.
Butterflies and Moths (Lepidoptera)
- Large white (Pieris brassicae) and small white (Pieris rapae) – The “cabbage whites” are the butterflies most frequently seen in gardens, where their caterpillars feed on brassica crops.
- Red admiral (Vanessa atalanta) – A striking migrant species that is now increasingly resident year-round in southern England.
- Large yellow underwing (Noctua pronuba) – Probably the most abundant moth in the UK. It is the large brown moth that commonly flies into houses through open windows on summer nights.
- Silver Y moth (Autographa gamma) – A migrant moth that arrives in massive numbers from the Continent each summer, visiting garden flowers at dusk.
Did you know? The total number of individual insects in the UK at any given time during summer is estimated to be in the trillions. Even a typical suburban garden may support thousands of insect species and millions of individual insects if all the microscopic species (thrips, springtails, parasitoid wasps) are included.
Other Common Groups
- Common earwig (Forficula auricularia) – Found under flowerpots, bark, and stones throughout the UK. Despite their pincers, earwigs are harmless to humans.
- Green shield bug (Palomena prasina) – Bright green in summer, turning bronze before hibernation. Increasingly common in gardens.
- Common froghopper (Philaenus spumarius) – The nymphs produce the familiar “cuckoo spit” froth on plant stems in spring. One of the most abundant insects in Europe.
- Common blue damselfly (Enallagma cyathigerum) – Abundant around ponds, lakes, and rivers from May to September.
Key Takeaway
The UK's most common insects include the black garden ant, seven-spot and harlequin ladybirds, crane flies, cabbage white butterflies, common wasps, bumblebees, and the large yellow underwing moth. These species are encountered so regularly that they provide an excellent starting point for anyone beginning to learn insect identification. Recognising these familiar species builds confidence and provides a foundation for exploring Britain's wider insect diversity.