Is it a drain fly?
The drain fly is a small, fuzzy-winged insect commonly found in moist indoor environments.
whichbug identifies insects from what you can see. It does not identify bites and has no health information.
What to look for
| Size | 1.5 to 5 mm |
|---|---|
| Colour | gray to black with a fuzzy appearance |
| Shape | broad, heart-shaped body when wings are folded |
| Wings | covered in fine hairs giving a moth-like appearance |
| Antennae | short and segmented |
| Movement | slow and erratic flight, often hovering near surfaces |
Where you'll find them
drain pipessewersunder sinksbathtub drainsmoist soil in potted plantsnuisance only
Does not damage property, food, or plants but indicates excess moisture.
Season: year-round, most active in warmer months
Signs it's around
- clusters of small dark insects on walls near drains
- visible larvae in drain slime
- adults resting on vertical surfaces near moisture sources
- presence of organic buildup in drains
Not sure? The lookalikes
| vs fruit fly | drain flies have fuzzy, heart-shaped wings while fruit flies have clear, transparent wings |
| vs fungus gnat | drain flies are larger and have a fuzzy, dark appearance compared to the slender, mosquito-like fungus gnat |
| vs moth | drain flies are much smaller and have a distinct heart-shaped wing posture when at rest |