Cluster flies: Information and advice

How to identify them 

  • These are dark greyish flies about 8mm long with yellowish hairs on the back and overlapping wings.
  • In autumn they congregate in large numbers in upper rooms or roof spaces of houses to hibernate.
  • A mass of cluster flies has a characteristic smell.
  • They are sluggish in flight and are a nuisance in the house.

Pest Control Cluster Fly

How they are treated ?


Cluster flies can often most easily be removed with a vacuum cleaner. Aerosol fly killers deal with smaller numbers. For larger infestations it is recommended that you contact our Pest Management Service.


Contact the pest control team for more information about treating commercial infestations.

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