Ferrets have an average lifespan between five and 10 years, with seven being advanced old age and 10 being unusually long-lived. Some ferrets may live 12 years. This information is based upon the lifespans of captive ferrets; ferrets are domestic animals, and they cannot survive for long in the wild.
Ferrets age rapidly, becoming sexually mature before they are a year old and showing signs of chronic illness related to aging as early as 3 1/2 years old. Adrenal disease affects up to a quarter of all ferrets older than four, leading to lifespan-shortening illness if left untreated. Other factors that can shorten a ferret's life include improper diet, neutering too early or not neutering at all, and lack of vaccinations to protect against common infectious diseases such as flu.