In warm weather, the leg-less white pupae (or maggots) emerge from their eggs in 8 to 20 hours. This larva goes through three stages of development within a week, or less during warmer seasons, up to 8 weeks during cooler times. The house fly maggot and eggs depend on damp organic material in which to develop and feed.
The pupa transforms into an adult in as little as 3 days or as long as 5 weeks. This pupation period varies with temperature and humidity.