Longest-living dog breeds: 20 that reach their late teens

PetMD’s analysis of dog breed life spans highlights a clear pattern: body size can predict canine longevity more reliably than many other traits. Great Danes and Newfoundlands often reach about seven to 10 years, while several smaller breeds can exceed 15. Three breeds—shih tzu, toy poodle, and Cavalier King Charles spaniel—top out at 18 years. The list is arranged by the upper end of each breed’s typical range, not as a ranking. PetMD notes the biology isn’t settled; one unproven idea is that managing age-related illness is harder in larger dogs. The record case is Bobi, a Portuguese Rafeiro do Alentejo, at 30 years—far beyond expected ranges.