What are the differences between flies and wasps?

Author(s)

David Britton
Updated

05/04/22
Read time

2 minutes

On this page...

Sometimes it is hard to tell the difference between flies and wasps at first glance. Both flies and wasps are winged, they both tend to 'buzz' around in the garden, and sometimes in the house, and some species can cause irrit

However, there are some key features that will help you to work it out.

Head/Eyes

Flies: Large, moveable head with large to very large eyes.
Wasps: Head not so large in proportion to body and eyes usually large.

Mouthparts

Flies: Sucking or piercing and sucking.
Wasps: Chewing (sometimes modified).

Antennae

Flies: Short to very short antennae (except in some species such as crane flies).
Wasps: Variable antennae - can be long and/or curled or relatively short.

Wings

This is the most obvious difference between flies and wasps, but wings can be hard to see when they are moving.

Flies: One pair of forewings, which are the only functional wings. The hindwings are reduced to club-like halteres.
Wasps: Two pairs of wings, with the hindwings smaller.

Thorax (mid-body section)

Flies: Middle segment of thorax (mesothorax) enlarged.
Wasps: Thorax not enlarged.

Waist

Flies: No distinct waist (except in some wasp/bee mimics).
Wasps: Distinct waist (except in sawflies).

Colour/markings

Colour and markings are not always reliable identification tools, but can be used in combination with other features.

Flies: Variable, black, brown, metallic blue or green. Wasp mimics can be striped black/yellow.
Wasps: Often have warning colours of striped black/yellow or brown/orange, but some species can be metallic blue/green.