Silverfish UK
Silverfish are small, fast-moving, wingless insects often found in damp UK bathrooms, kitchens, basements, cupboards and lower-ground flats. Repeated sightings can suggest high humidity, condensation, leaks, poor ventilation or hidden harbourage.
Bon Accord Pest Control provides professional silverfish inspections, treatment and prevention advice for London homes, landlords, commercial premises and managed buildings.
Quick answer: what are silverfish?
Silverfish are small, silver-grey, wingless insects that move quickly and often appear in damp, dark places. They are usually found in bathrooms, kitchens, basements, cupboards, behind skirting boards, under flooring, around pipework and near areas with condensation or poor ventilation.
Fast-moving
Silverfish move quickly and usually disappear into cracks, floor edges or under skirting when disturbed.
Moisture linked
Repeated sightings often point to damp, humidity, condensation, poor ventilation or hidden leaks.
Damage risk
They may damage paper, wallpaper, cardboard, book bindings, packaging and some fabrics.
What do silverfish look like?
Silverfish have a distinctive appearance. They are usually silver-grey or metallic in colour, long and narrow, flattened, wider at the head and narrower towards the tail. They have long antennae and three tail-like bristles at the back.
| Feature | Typical appearance |
|---|---|
| Body | Flattened, carrot-shaped, silver-grey and wingless. |
| Size | Often around 10–15mm, although exact size varies. |
| Movement | Fast, wriggling, fish-like movement, usually at night. |
| Tail | Three noticeable tail-like bristles at the rear. |
Are silverfish common in the UK?
Yes. Silverfish are common in UK homes and buildings, including houses, flats, student accommodation, hotels, offices, libraries, storage rooms, restaurants and older buildings.
In London, silverfish are frequently linked with older properties, basement flats, poor bathroom ventilation, leaks under baths or sinks, pipe boxing, communal blocks, damp cupboards and stored paper or cardboard.
Why do I have silverfish in my home?
Silverfish usually appear when the property provides moisture or humidity, shelter and cracks to hide in, and food sources such as starch, glue, paper, dust or crumbs.
- Poor ventilation in bathrooms
- Condensation around windows or cold walls
- Leaks under baths, sinks or appliances
- Damp behind tiles or bath panels
- Pipework voids
- Loose wallpaper or damaged plaster
- Stored cardboard boxes
- Books, papers or files in damp areas
- Crumbs, dust or organic debris
- Basements and lower-ground flats
Are silverfish a sign of damp?
Silverfish can be a sign of damp or high humidity, especially when they are seen repeatedly in bathrooms, kitchens, basements, utility areas or around pipework. They prefer humid conditions and often hide close to cracks, crevices, loose flooring, damp plaster, bath panels, skirting boards and wallpaper.
Check moisture
Look for condensation, damp staining, mould, peeling wallpaper, leaks and poor airflow.
Find harbourage
Silverfish hide behind skirting, bath panels, flooring, tiles, pipe routes and storage areas.
Treat properly
Control should combine inspection, moisture correction, cleaning and targeted treatment.
Where do silverfish live?
Bathrooms
Bathrooms provide moisture, warmth and hidden cracks around baths, basins, tiles, pipework and flooring.
Bedrooms
Bedroom silverfish are often linked with adjoining bathrooms, humidity, stored paper, wardrobes, dust or external damp walls.
Kitchens and cupboards
Kitchens provide food residues, paper packaging, cardboard, sink pipework, appliance voids and moisture sources.
Silverfish in the bathroom
Bathrooms are one of the most common places to find silverfish. You may see them in the bath or shower tray, around the toilet base, behind a basin pedestal, along skirting boards, near cracked grout, around pipe boxing or under bath panels.
To reduce bathroom activity, improve ventilation, repair leaks, dry wet areas, remove dust and hair build-up, and avoid leaving damp items on the floor. If activity continues, the problem may be hidden behind panels, tiles or voids.
Silverfish in bedrooms, kitchens and cupboards
Bedrooms
Silverfish in a bedroom are not bed bugs and do not feed on blood. Check wardrobe corners, skirting boards, under the bed, stored boxes, books, paperwork, damp external walls and en-suite bathrooms.
Kitchens
Silverfish may hide under appliances, behind kickboards, around sink pipework, in cupboards and under flooring. Keep dry foods sealed, remove waste cardboard and check for leaks.
Silverfish in basements and lower-ground flats
Basements and lower-ground London flats are especially attractive to silverfish because they are often cooler, darker and more humid. Even when the visible living area looks clean and dry, moisture can remain behind walls, under flooring or around service routes.
- Repeated sightings near skirting
- Silverfish trapped in baths or sinks
- Activity around external walls
- Damp smell, mould or staining
- Peeling wallpaper or damage to stored paper
Common silverfish vs grey silverfish
Most people describe any silver-grey, fast-moving bristletail insect as a silverfish. However, there can be more than one species involved.
| Type | Why it matters |
|---|---|
| Common silverfish | Strongly associated with damp, humidity and moisture. Often found in bathrooms, kitchens and basements. |
| Grey silverfish | May survive in lower humidity and can appear in living rooms, bedrooms, offices, storage rooms and libraries. |
A professional inspection can help assess whether the activity is likely to be a standard moisture-linked silverfish problem or something more widespread.
Are silverfish harmful?
Silverfish are not known for biting people and they are not usually treated as a major public health pest. However, they can still be a problem because they may damage wallpaper, books, paperwork, cardboard boxes, stored documents, photographs, book bindings, packaging and some fabrics.
A single insect in a bathroom may be a minor nuisance. Repeated sightings, visible damage, activity in several rooms or activity in commercial storage, libraries, offices or hotels should be investigated.
What are the signs of a silverfish infestation?
- Seeing live silverfish at night
- Silverfish trapped in baths, basins or sinks
- Small irregular marks on paper or wallpaper
- Damage to book bindings or stored paper
- Activity near skirting boards
- Shed skins
- Tiny dark specks in harbourage areas
- Repeated sightings in damp rooms
- Insects appearing from cracks, gaps or floor edges
- Damage to cardboard or packaging
Image guide: where silverfish activity appears
Bathroom activity
Silverfish are often seen near baths, sinks, pipework, cracked grout and damp floor edges.
Damp and harbourage
Repeated sightings may point to moisture, condensation, leaks or hidden voids.
Professional inspection
Good treatment begins with identifying harbourage, movement routes and the underlying conditions.
How to get rid of silverfish in the UK
The best silverfish control combines inspection, moisture reduction, cleaning, proofing and targeted treatment where needed.
- Identify where they are being seen.
- Check for leaks under sinks, baths and appliances.
- Improve ventilation in bathrooms and kitchens.
- Reduce condensation.
- Remove damp cardboard, paper and clutter.
- Vacuum edges, cracks and hidden dust.
- Store dry foods in sealed containers.
- Seal obvious cracks and gaps after inspection.
- Arrange professional treatment if sightings continue.
Professional silverfish pest control
A professional silverfish treatment should not be a quick generic spray. It should begin with an inspection and a plan.
Inspection first
We assess where silverfish are being seen, whether the issue is localised or widespread, and what conditions may be supporting activity.
Targeted treatment
Treatment may involve careful application to cracks, crevices, harbourage areas and movement routes where appropriate.
Prevention advice
We advise on moisture, ventilation, storage, proofing and practical steps to reduce repeat activity.
Silverfish treatment in flats and managed buildings
Silverfish can be more complicated in blocks of flats, converted houses and managed buildings because activity may be linked to communal pipe routes, service risers, ventilation issues, older construction or repeated damp conditions.
For landlords, managing agents and tenants, the best approach is to record where insects are seen, which rooms are affected, whether other flats report the same issue, any damp or ventilation problems, photos of insects and dates of sightings.
Silverfish in commercial premises
Silverfish may affect hotels, restaurants, offices, archives, museums, libraries, retail stockrooms, schools, nurseries and storage areas. Commercial activity can be linked to damp storage rooms, paper records, cardboard stock, staff bathrooms, kitchens, welfare areas, basement storage, plant rooms and service voids.
Businesses should act early before silverfish spread into customer-facing areas, stored stock or sensitive paper records.
What not to do
- Do not ignore repeated sightings.
- Do not spray randomly without finding the source.
- Do not leave damp cardboard in cupboards.
- Do not store paper directly on damp floors.
- Do not assume silverfish are caused by poor cleanliness.
- Do not ignore condensation or leaks.
- Do not seal every gap before inspection if insects are still active.
When should you call pest control?
Call a professional if you are seeing silverfish repeatedly, several rooms are affected, you see them outside bathrooms or kitchens, there is damage to books or paper, you manage a rental or commercial property, DIY treatment has failed, you suspect grey silverfish, or there is damp, mould or poor ventilation.
Send photos for silverfish identification
If you are not sure whether the insect is a silverfish, take a clear photo and send it to Bon Accord. Include a close-up photo, a wider location photo, details of where it was found, how often you are seeing them, and any photos of damp, damage or cracks.
FAQ: Silverfish UK
What are silverfish?
Silverfish are small, fast-moving, wingless insects with a silver-grey body, long antennae and three tail-like bristles. They are often found in damp, dark places such as bathrooms, kitchens and basements.
Are silverfish common in the UK?
Yes. Silverfish are common in UK homes and buildings, especially in bathrooms, kitchens, basements, cupboards and other areas with moisture, cracks or stored paper.
Are silverfish a sign of damp?
Silverfish can be a sign of damp, condensation, leaks or poor ventilation, especially when they are seen repeatedly. Grey silverfish may survive in drier rooms.
Do silverfish bite?
Silverfish do not normally bite people and are not considered a major health risk. They are mainly a nuisance pest and can damage paper, wallpaper, books, cardboard and some fabrics.
Why do I keep seeing silverfish in my bathroom?
Bathrooms provide moisture, warmth and hidden cracks around tiles, pipework, bath panels and skirting boards. Poor ventilation, condensation or small leaks can make activity worse.
How do I get rid of silverfish?
Reduce humidity, improve ventilation, repair leaks, remove damp cardboard or paper, vacuum cracks and edges, seal gaps where appropriate and use professional targeted treatment if activity continues.
Can silverfish damage property?
Yes. Silverfish can damage paper, wallpaper, books, cardboard, book bindings, packaging and some textiles because they feed on starches, sugars and glue-based materials.
What is the difference between silverfish and grey silverfish?
Common silverfish are more strongly linked with damp and humidity. Grey silverfish can survive in drier conditions and may be found in living rooms, bedrooms, storage rooms and offices.
Should landlords deal with silverfish?
Responsibility depends on the cause. If silverfish are linked to damp, leaks, ventilation defects or building issues, landlords or managing agents may need to investigate and correct the source.
Does Bon Accord Pest Control treat silverfish in London?
Yes. Bon Accord Pest Control provides silverfish inspection, treatment and prevention advice for London homes, flats, landlords, commercial premises and managed buildings.
Step by Step
Once the source of the problem has been identified, you’ll need to take steps to eliminate their food sources. Silverfish feed on a variety of items, including wallpaper paste, paper, glue, and fabric. Vacuum or sweep all of these areas regularly to reduce their food supply. Next, you’ll need to reduce the moisture levels in the affected areas. Silverfish thrive in humid environments, so use a dehumidifier to reduce the humidity in your home. You can also remove any standing water around the house, such as in flowerpots, gutters, and crawl spaces.
