Drain flies are tiny insects that like to live in the slime that builds up inside drains. This article shows easy steps to remove them and keep them from coming back, so your home stays clean.

The flies breed in gelatinous slime in drain pipes and other damp places such as sewer leaks, garbage bins, and air‑conditioner drainage outlets. Although they do not spread disease, their presence shows the area is not clean.

The first step is to scrub away the slime. Faith Oi, PhD, says to use a stiff drain brush or a drain snake and to clean the ridges and crevices. This removes the food and any eggs or larvae.

After the slime is gone, an enzyme‑based drain cleaner can break down any remaining residue. Pest‑control expert Eliot Moakes recommends using the cleaner after the visible blockages are cleared.

To stop flies from returning, keep pipes free of buildup, remove standing water, and flush drains that are rarely used. Essential oils and ultrasonic devices have no scientific proof, so removing the slime is most important. If flies keep coming, ask a plumber or pest‑control professional for help.