How do you get rid of fruit flies?

Fruit flies breed in fermenting organic film, and a single overlooked source keeps regenerating them, which is why swatting feels endless. Hunt the source first: overripe fruit and potatoes or onions in a bin, the residue inside a sink drain or garbage disposal, the sticky bottom of a trash or recycling can, a mop bucket, damp rags, drip trays under appliances, and the last inch in returnable bottles and cans. Scrub drains with a brush and hot soapy water rather than just running water, since the film clings to the pipe wall above the water line.

While you clear the source, thin the adults with a trap that genuinely works: a small dish of apple cider vinegar with a drop of dish soap, which breaks the surface tension so flies sink instead of landing and leaving. Cover with plastic wrap poked with a few small holes if you want it tidier. Refrigerate ripe produce during an outbreak, take out the trash daily, and rinse recyclables. Because the whole egg-to-adult cycle runs about a week in a warm kitchen, expect a few days of stragglers after you have fixed the source, and only worry if flies persist beyond two weeks, which suggests a breeding site you have not found.