Flies, which belong to the order Diptera, undergo a complete metamorphosis. Put another way, this means that baby flies look and act totally different than adult flies.

Immature flies, called maggots, hatch and go through the larval and pupal stages before becoming adults. Where these baby flies hatch will depend on their individual species, but there are some commonalities across the different types of flies.


The majority of fly species lay their eggs in locations that would offend the noses of most people. That’s because fly females look for damp, rotting organic wastes, deceased animals or animal excrement to deposit their eggs. The maggots develop by eating the bacteria associated with these environments. There are some species, however, that develop by eating other insects. For example, hover fly larvae prey on aphids and other small gardening pests. Hover flies are considered beneficial pollinators, unlike the nuisance flies often seen inside your home.

A baby fly is typically very small, though some can grow up to one-half of an inch in length. They are usually a whitish, creamy color and resemble small worms or grubs. They are legless, wingless and crawl around in search of food. When they have reached full size, they hunt for a place to pupate. In the pupal stage, they will develop into adults.

Flies develop quickly, especially in the summer months when conditions are ideal; most species develop from larvae to adults in seven to 14 days.


While you are more likely to see adult flies than you are baby flies, the larval stage is the best time to control their population. The most effective way to do this is by reducing breeding locations. By cleaning trash cans, garbage disposals, outdoor pet environments and other locations where flies are known to lay eggs, you break their life cycle.