Cluster Fly Pest Control
Cluster flies can be a frustrating nuisance, especially when they invade homes in large numbers. Our professional pest control services are designed to eliminate infestations quickly, giving you peace of mind.
Are flies suddenly appearing in your loft? It could be Cluster flies.
What Are Cluster Flies?
Cluster flies (typically refering to Pollenia rudis) are slow-moving flies that often gather in large numbers inside homes, especially around windows, attics, and loft spaces. Unlike house flies, cluster flies are not attracted to food waste — instead, they seek out warm, quiet areas to hibernate. Their presence can be unsettling, and large infestations are common in autumn and winter months.
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As full members of The British Pest Control Association, you can be assured that we are both trained & qualified. We are fully insured and follow all industry Code of Best Practice, using only the most humane and effective methods available.
Signs of a Cluster Fly Infestation
One of the most obvious signs of a cluster fly infestation is a sudden appearance of large, sluggish flies, especially on sunny days. You may notice them around windows, light fixtures, or in rarely used rooms. Their presence is often most noticeable in lofts, roof voids, and upper floors.
How to Get Rid of Cluster Flies
Low numbers of cluster flies may be manageable with DIY fly spray. But as the numbers increase it can be challenging without professional help. Our pest control technicians use safe, effective insecticide treatments to the effected area to target both visible flies and those hidden in wall voids or roof spaces. We can quickly reduce large numbers and restore comfort to your home or workplace.
Professional Cluster Fly Removal Services
If you’re dealing with a persistent cluster fly problem, professional pest control is the most effective solution. Our trained technicians have extensive experience dealing with cluster fly infestations in residential and commercial properties. We use industry-approved insecticides and methods to ensure thorough removal.
Why Choose Our Cluster Fly Control Service?
We offer fast response times, discreet service, and proven treatments for cluster fly infestations. Whether you’ve found a few flies or are facing a full-scale infestation, our team is here to help with reliable, expert solutions that get results.
Cluster Fly UK Species
Cluster flies are a common nuisance across the UK, particularly during the colder months when they seek shelter in homes, lofts, and other buildings. Unlike house flies, they don’t pose a direct health risk, but their sheer numbers and persistence can make them a real problem.
Common Species of Cluster Fly
Cluster Fly (Pollenia rudis)
The most widespread species, recognisable by its dark grey body flecked with golden hairs. These flies feed on earthworms outdoors but move inside in autumn to hibernate in large numbers. You can therefore notice peaks as they enter in autumn, and leave in springYellow Swarming Fly (Thaumatomyia notata)
A smaller species with distinctive yellow markings. Often seen in huge swarms, particularly around windows and sunny walls. Despite their size, they can invade lofts and wall voids in astonishing numbers.Autumn Fly (Musca autumnalis)
Very similar in appearance to the house fly, but typically found outdoors in summer feeding on livestock. As temperatures drop, they gather in buildings to overwinter in large groups.Green Cluster Fly (Dasyphora cyanella)
A metallic green species that may be mistaken for a blowfly. Though less common than Pollenia rudis, it also seeks refuge indoors when the weather turns cold.
Other Overwintering Guests
Cluster flies are the main culprit, but other insects also can be found overwintering in lofts.
As the temperatures drop, queen wasps and hornets often crawl into attics and roof voids, where they hunker down alone until spring. Alongside them, you may find green lacewings, they gather in clusters, sometimes in surprisingly large numbers. Ladybirds are also frequent visitors, with both native species and the invasive Harlequin ladybird known to group together in window frames, rafters, and hidden cracks as they ride out the winter.
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Every branch is run by local pest professionals who live and work in your area. We know your community, and your pest problems – better than anyone.
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Our proven pest control process
Our process is built around expertise, safety, and long-term results. From the first inspection to prevention, every step is tailored to your property and pest issue.
Inspection & Assessment
We begin with a detailed inspection to identify the pest, assess the severity, and locate entry points or food sources. This helps us plan the best next steps.
Tailored Cluster Fly Control Plans
Each fly infestation is unique. We design custom treatment plans based on the type of fly, extent of damage, and property layout, whether in your home, business, or storage areas.
Safe & Eco-Friendly Solutions
As BPCA members, we prioritize safe, non-toxic pest control wherever possible — protecting your property without harming wildlife or the environment.
Ongoing Prevention & Maintenance
We offer preventative measures like sealing entry points, traps, or monitors — helping stop pests from coming back and giving you long-term peace of mind.
Let’s Get Your Cluster Fly Problem Under Control Today
No more guessing, no more damage. Let our trained professionals assess your space and implement a treatment that works.
- Fully Qualified & Accredited BPCA Members
- Domestic & Commercial Pest Control Services
- Comprehensive Pest Coverage
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Frequently asked questions
Why do I have cluster flies in my loft every winter?
Cluster flies gather indoors during the colder months to overwinter in sheltered spaces like lofts, attics, and roof voids. Unlike house flies, they don’t breed or feed indoors — they’re simply hibernating.
Chances are you live near some grass fields nearby, that is likely the source.
Are Cluster Flies dangerous to humans?
No — cluster flies are not considered a health risk in the same way as house flies or bluebottles. They don’t feed on waste or spread bacteria. The main problem is their sheer numbers, the mess they leave behind, and the frustration of dealing with repeated infestations.
How can I tell if the flies in my loft are cluster flies or something else?
Cluster flies are dark grey with golden hairs on their thorax and fly more sluggishly than house flies. They also gather in large groups. Other insects, such as bluebottles, wasp queens, ladybirds, or green lacewings, may also be found in lofts over winter, but these usually appear in smaller numbers. A professional inspection can confirm what species you’re dealing with.
Can I get rid of cluster flies myself, or do I need pest control?
Small numbers of cluster flies can sometimes be dealt with using a vacuum or aerosol spray. However, larger infestations require professional treatment to properly target loft voids and hidden cavities.
When do cluster flies appear?
Cluster flies are most noticeable in autumn and spring. In the autumn, they appear on warm sunny days as they gather on walls, windows, and roof spaces, searching for a way into lofts and other sheltered areas to hibernate. Once inside, they remain dormant through the coldest months, but in spring they reappear, often buzzing around windows or loft spaces as they wake up and leave to continue their life cycle outdoors. This is why many homeowners notice cluster flies twice a year — first when they come in, and again when they head back out.
How do I stop cluster flies and other insects from overwintering in my loft?
If there is a clear entry point then the best prevention is proofing. Sealing gaps, vents, and cracks where insects can enter.
In many properties, the very design and construction of the roof give cluster flies endless opportunities to slip inside — meaning proofing isn’t always realistic. The most effective long-term approach in these cases is to treat the affected loft space each winter. Regular, consistent treatments reduce the population year after year, so you’ll notice fewer flies returning each season. Over time, this consistent control strategy makes infestations much more manageable.