Foster period lengths depend on why the pet needs a foster home and how the organization finds homes for its adoptable pets. The average foster period is about a month. Some pets only need a foster family for a week or so. (ie while they waiting to be transported to an adopter or rescue group out of the area.) Other pets, such as moms with babies, pets undergoing medical treatment and pets who need foster homes until they are adopted will likely need longer, sometimes two to three months. Talk with the animal rescue organization who is caring for the pet to find how long they think they will need you to foster.
Keep in mind that sometimes things don’t work out as planned. A foster pet may need unanticipated medical care, or recovery time may take longer than expected. Pending adoptions can fall through or fail. Or it may take longer than expected for cage space to open up at the shelter. If you are asked to foster a pet and have a limited time frame due to an upcoming vacation, etc., please discuss this with the rescue organization up front.