Silverfish don’t bite and don’t spread disease, but they’re a genuine nuisance once established — and their presence is often a sign of an underlying damp or humidity issue worth addressing alongside treatment. They’re most commonly found in bathrooms, kitchens, basements, and lofts, anywhere consistent moisture gives them the environment they need to thrive.

Signs of a silverfish infestation

• Small, silvery, fish-shaped insects seen scurrying away quickly when a light is switched on, usually at night
• Small irregular holes or “notches” in paper, cardboard, book bindings, or wallpaper glue
• Yellowish stains or tiny black droppings (pepper-like specks) near skirting boards or in cupboards
• Consistently damp or humid conditions in the affected room — silverfish rarely establish in genuinely dry spaces

Why silverfish keep coming back

Treating visible silverfish without addressing the underlying moisture almost always means the problem returns. Silverfish need consistent humidity to survive and reproduce, so a bathroom with poor ventilation, a leaking pipe under a kitchen sink, or a damp loft will keep attracting new activity even after a treatment kills the current population.

Our Silverfish Control Process

1. Inspection — identifying affected rooms, likely harbourage points (behind skirting, under baths, in loft insulation), and any obvious moisture sources.
2. Treatment — residual insecticide spray targeted at cracks, crevices, and known hiding spots.
3. Moisture and prevention advice — practical guidance on ventilation, dehumidifying, and fixing any damp sources identified during inspection, since this is what actually stops recurrence.
4. Follow-up, where the infestation is more established, to confirm activity has stopped.

What does silverfish control cost in London?

Silverfish treatment in London typically starts from around £180–£260, usually resolved in a single visit for light to moderate infestations, with more extensive or recurring problems (often linked to unresolved damp) needing a follow-up visit. We’ll confirm the exact price and likely number of visits after inspection.

Common in These London Areas

Silverfish are a frequent call-out across North West London and North East London, particularly in older properties with bathrooms and lofts prone to humidity. Check your area page for local detail, or contact us directly.