The larvae of drain flies live and feed on the dirt and sludge inside your drains, especially scummy drains that need a good cleaning. Please do not take offense to this but come on; none of us can claim perfectly clean drains!

The female drain fly lays her eggs in the rotting, slimy, oozing muck or scum that builds up in drain pipes.

Adult drain flies are tiny, dark flies that fly in short hops or hover around drain.  They have hairy wings like a moth, although they are much smaller which is why sometimes they are also known as moth flies.


You may have seen a few drain flies resting on walls in your bathroom around the sink or bathtub and didn’t pay them much attention. Drain flies can often be confused with fruit flies.

Drain flies can breed in the sink, bathtub, and shower drains, as well as in sump pumps, basement floor drains, even in scummy garbage cans or refrigerator drip pans.

If you find you have an issue with drain flies, please contact our office staff and they will kindly email you our fact sheet on how you can take steps to eradicate these dirty drain flies yourself.