Booklice are tiny, pale and easy to miss until they appear in numbers. Here is how to recognise them and tell them apart from other small insects.
Booklice are not lice and they do not live on people or pets. They are very small, soft-bodied insects, usually one or two millimetres long, pale grey, cream or almost translucent. Most indoor species are wingless, which makes them look a little like a speck of moving dust until you see them on a dark surface. They run quickly and often in short bursts.
Booklice feed on microscopic mould and fungi, and on starchy or paper-based material that has gone slightly damp. That includes old book bindings, wallpaper paste, cardboard boxes, stored food such as flour or cereal, and the surface mould that can form on walls and window frames.
Bed bugs are larger, flat, reddish-brown and found near sleeping areas. Dust mites are even smaller and cannot be seen without magnification. Springtails jump when disturbed, while booklice run. Young silverfish are longer and carry tail filaments. If you can catch one on sticky tape and look at it under a magnifier, you will usually be able to settle the question.
Booklice do not bite, do not spread disease and do not eat through wood or fabric. Their presence is mainly a nuisance. They can contaminate stored food and mark paper, and a large population is a clear sign that something is keeping a space too humid.
Place a sheet of dark paper or a strip of sticky tape in the suspect cupboard or shelf overnight, then look at it in the morning with a magnifying glass. Booklice that have wandered onto it will show as small pale specks with large heads and long, thin antennae. A handful suggests a minor issue, while dozens point to an established colony.
Photograph the insects next to a coin for scale. That gives a technician a good starting point if you decide to ask for help, and helps to rule out species that need a different approach.
Do not confuse a booklice colony with a single stray insect. One or two on a windowsill after rain are not unusual, whereas a steady, repeating presence in the same spot suggests a food source nearby.
If you have found tiny insects and are not sure what they are, we can identify them and check where the moisture is coming from. We survey homes and businesses in Leeds and West Yorkshire free of charge. Call 0113 347 0014 or message us on WhatsApp and we will arrange a quote.
No. Booklice are not related to head lice and do not live on people. They are tiny insects found in damp rooms and on mouldy or starchy material. They do not bite and are not harmful to health.
Newly built or recently plastered houses can hold a lot of moisture while the walls dry, and that encourages the mould booklice eat. Numbers usually fall as the building dries out and is properly ventilated.
Look closely at a specimen. Booklice are pale, soft-bodied and one to two millimetres long, and they run rather than jump. If you cannot decide, we can identify the insect from a sample or at a survey.
Tell us what you have seen and where, and we will come back to you. There are no call-out charges and surveys are free for homes and businesses.
