List of woodlice of the British Isles

Woodlice are the most species-rich group of terrestrial crustaceans.

One of these species, Acaeroplastes melanurus, had been considered extinct in the British Isles but was rediscovered in 2002 at its only site (Howth, County Dublin, Ireland), and a further ten species have become naturalised in greenhouses, presumably transported with exotic plants.

"Pill bugs" of the family Armadillidiidae are often confused with pill millipedes such as Glomeris marginata, which is also widespread and common in Britain and Ireland, but pill millipedes have two pairs of legs per body segment, while woodlice have only seven pairs of legs.

[5] Six certainly native species occur in the British Isles; some doubt exists as to the status of Eluma caelatum.

Haplophilosciidae is a family of woodlice lacking pleopodal lungs.