How long a dog flea survives depends on several factors. The average flea survives a few days to two weeks without a food supply, and they can live much longer with a host.
Fleas survive an average of eight days on a short-haired dog, and they typically last longer on a host with longer hair. Fleas need a food source to survive and reproduce to continue their life cycle, and a healthy flea can lay around 27 eggs each day. To break the life cycle of fleas, pesticides are often used to break this cycle by killing the fleas and their eggs.