A cat’s home range is the area that the cat normally uses in its daily activities. A home range is different from a territory in that it may not be defended from other cats, but non-biologists frequently use the terms interchangeably. When an outdoor-access cat goes missing, it probably means that something has happened to prevent the cat from coming home. Some of the possible circumstances that could prevent a cat from coming home include being injured or killed by a vehicle or predator, hiding due to illness or becoming trapped somewhere. Under these circumstances the lost cat is probably still present within its own home range. Missing Pet Partnership suggests that owners of lost outdoor-access cats should search their cat’s territory. However, most cat owners do not have an accurate understanding of where their cat travels when it is let outside the house. I researched the scientific literature and compiled a summary of the mean home ranges of owned and free-ranging domestic cats in urban/suburban and rural areas. Free-ranging cats may be lost, stray, feral or farm cats. Please see the attached file for a summary of results and literature reviewed. In general, I found that these home range summaries conformed well with Missing Pet Partnership’s recommendation of physically searching for a lost cat within a three to five house radius from the cat’s home.