The average lifespan of a flea is 30 to 90 days, but with a good food supply they have been known to make it to over a year! A female flea can lay up to 30 eggs a day, and they can be viable up to 200 days. The larvae live about 12 days.
In most circumstances a flea can live for a few months, but under ideal conditions one can live for over a year if temperature and food supplies are right.