Are they really those tiny fruit flies, or those slightly bigger black ones that rest on the wall?

There is a very small fly which I was told comes from our drains.

At any rate, you might try running some very hot water or a bit of bleach down your drains.

Just a thought...

We just had this problem about two months ago. My hubby found internet advice that said to make a funnel out of a piece of paper and place it in a jar with a piece of fruit in the bottom(we used banana)then seal the rim with tape. It seems the flies can get in but aren't smart enough to get out. I was skeptical but tried it and it actually worked. Haven't had any for about a month now. We had to leave the jar out for about three weeks though to take care of any newly hatched ones before they could breed so I don't know how much this will help before tomorrow (might take care of many of the adult ones though so you have less flying around).

Good luck!

I just went through a very frustrating week of the same thing. I found a rotting potato hiding in the back of a cabinet (where my potatoes are usually stored). I tossed it out, washed the cabinet interior, and no more little flies! Do a search in your kitchen, they are coming from something.