Female lays 5-6 batches of 75-120 oval, white eggs on moist manure or garbage. Eggs hatch in 10-24 hours. Larvae reach full size in 5 days emerging as adults about 5 days latter. They are ready to mate within a few hours after emerging. During warm weather two or more generations may be completed in a month. Males live for 15 days, females up to 26 if they have access to milk, sugar, and water.

too long.

Common Housefly Life Cycle;

Each female fly can lay up to 500 eggs (in five batches of 100 eggs each). The eggs are white and are about 1.2 mm in length. Within a day, the larvae (maggots) hatch from the eggs; they live and feed in (usually dead and decaying) organic material, such as garbage or feces. They are pale whitish, 3-9 mm long, thinner at the mouth end, and have no legs. At the end of their third instar, the maggots crawl to a dry cool place and transform into pupae, colored reddish or brown and about 8 mm long. The adult flies then emerge from the pupae. (This whole cycle is known as complete metamorphosis.) The adults live from half a month to a month in the wild, or longer in benign laboratory conditions. After having emerged from the pupae, the flies cease to grow; small flies are not young flies but the result of insufficient food during the larval stage.
Some 36 hours after having emerged from the pupa, the female is receptive for mating. The male mounts her from behind to inject sperm. Normally the female mates only once, storing the sperm to use it repeatedly for several sets of eggs. Males are territorial: they will defend a certain territory against other males and will attempt to mount any females that enter that territory.


Housefly pupae killed by parasitic wasp larvae. Each pupa has one hole through which a single adult wasp emerged; feeding occurs during the wasp's larva stage.
The flies depend on warm temperatures; generally, the warmer the temperature the faster the flies will develop. In the winter, most of them survive in the larval or pupa stage in some protected warm location.
Some species of wasps can parasitize and kill the pupae.

The lifespan of a fly depends on your AIM!

The average fly will live for 36 hours. Unless it is swatted.

ill different because they never know what day there gonna get swatted or taken by a frog!!

If i fly isnt puposfully killed by a human or another animal, they can often live up to 36-56 years. This doesnt often happen because they are usually killed but... i know that they can live up to this age because once, i found a baby fly and put it in a big big cage... and it lived for 56 years!!! :)

five days

I have heard anywhere between 24 -48 hours.

I love science. Thats what I do for a living, work at a biotech company. Im going into medicine though. :-)