The overall life cycle of the house fly (from egg to adult) is about 7–10 days in the summer in warm temperate areas.
As stated in the previous sections, rates of development of each stage are dependent upon temperature.
Often the temperature of the decaying and fermenting larval medium is considerably higher than the prevailing air temperature, however, so that development occurs much faster than anticipated by the climatic conditions.
The times required for completion of development may be expressed as degree-hours or degree-days which are the multiple of time (hours or days) and number of degrees of temperature (°C or °F) above the threshold temperature for development.
Typical values for the life stages of the house fly are:
| egg |
7.4 hour-°C (13.3 hour-°F) |
| larva |
132 day-°C (237.6 day-°F) |
| pupa |
87 day-°C (156.6 day-°F) |
| pre-oviposition |
45 day-°C (81 day-°F) |
Typical days required for the total life cycle at various temperatures are:
| °C |
°F |
Avg. No. |
Days (range) |
| 16 |
61 |
44.8 |
(40 – 49) |
| 18 |
64 |
26.7 |
(23 – 30) |
| 20 |
68 |
20.5 |
(19 – 22) |
| 25 |
77 |
16.1 |
(14 – 18) |
| 30 |
86 |
10.4 |
(9 – 11) |
| 35 |
95 |
7.0 |
(6 – 8) |
| 
