The United Kingdom is home to 59 regularly breeding butterfly species, with a handful of additional migrants and rare vagrants. While this is a modest number compared to tropical regions, it makes butterfly identification an accessible and rewarding pursuit. By learning the features of the 15–20 most common species, you can identify the vast majority of butterflies encountered in British gardens, parks, and countryside.
Key Identification Features
When identifying a butterfly, note the following features:
What to Look For
- Wing colour and pattern — both upperside (when wings are open) and underside (when closed)
- Size — wingspan can help distinguish similar species
- Flight period — the months when adults are on the wing
- Habitat — woodland, grassland, garden, hedgerow, etc.
- Behaviour — basking posture, flight style, flower preferences
- Caterpillar food plants — useful for confirming identity if eggs or larvae are found
Common Garden Butterflies
| Species | Wingspan | Key Features | Flight Period |
|---|---|---|---|
| Large white (Pieris brassicae) | 58–63 mm | White with black wingtips; female has two black spots on forewing | April–October (2 broods) |
| Small white (Pieris rapae) | 46–54 mm | Smaller than large white; single black spot on forewing upperside | March–October (2–3 broods) |
| Red admiral (Vanessa atalanta) | 64–72 mm | Black with bold red bands and white spots near forewing tips | May–October (migrant) |
| Painted lady (Vanessa cardui) | 58–74 mm | Orange-brown with black spots and white patches; mottled underside | May–October (migrant) |
| Peacock (Aglais io) | 63–69 mm | Dark red-brown with four prominent eyespots (one per wing) | March–October; hibernates as adult |
| Small tortoiseshell (Aglais urticae) | 45–62 mm | Orange with black, yellow, and blue markings; scalloped wing edge | March–October; hibernates as adult |
| Comma (Polygonia c-album) | 50–64 mm | Ragged wing edges; underside has white comma-shaped mark | March–October; hibernates as adult |
The “Cabbage Whites”
The large white and small white — collectively called “cabbage whites” — are the butterflies most commonly seen in British gardens. They are often considered pests because their caterpillars feed on brassica crops (cabbages, broccoli, Brussels sprouts). The green-veined white (Pieris napi) looks similar but has dark veins on the underside of the hindwing and its caterpillars feed on wild crucifers rather than cultivated brassicas.
Grassland and Meadow Species
Open grasslands support several distinctive species:
Meadow Brown (Maniola jurtina)
Britain’s most abundant butterfly. Brown with a single eyespot on the forewing upperside (orange-ringed in the female). Flies from June to September in meadows, verges, and rough grassland.
Gatekeeper (Pyronia tithonus)
Similar to the meadow brown but smaller and more orange, with a double-pupilled eyespot on the forewing. Common along hedgerows in July and August.
Common Blue (Polyommatus icarus)
Males are bright violet-blue above; females are brown with orange spots along the wing margins. Found in grasslands where bird’s-foot trefoil (the caterpillar food plant) grows. Flies May–September in two broods.
Did you know? The orange-tip butterfly (Anthocharis cardamines) is one of the earliest spring butterflies, flying from April to June. Only the male has the bright orange wingtips; the female is white with grey-green marbling on the underside, and is often mistaken for a small white.
Woodland Species
Woodland edges, rides, and clearings support species such as the speckled wood (Pararge aegeria), which is brown with cream spots and patrols dappled sunlit patches, and the ringlet (Aphantopus hyperantus), which is dark brown with small eyespots on the underside and flies in shady, damp grassland near woodland.
Step-by-Step Identification Process
- Note the colour. White? Orange? Brown? Blue? This immediately narrows the possibilities.
- Check for key markings. Eyespots, coloured bands, wing-edge patterns, and underside markings are diagnostic.
- Estimate the size. Small (under 40 mm), medium (40–60 mm), or large (over 60 mm) wingspan.
- Record the date. Many species have well-defined flight periods that aid identification.
- Note the habitat. Garden, meadow, woodland, or hedgerow? Each favours different species.
- Photograph both sides. The upperside and underside patterns are often very different and both may be needed for identification.
Key Takeaway
With just 59 resident species, UK butterfly identification is accessible to beginners. Focus on wing colour, key markings, size, flight period, and habitat. Learning the 15–20 most common species will allow you to identify the vast majority of butterflies encountered in everyday British habitats.