Terrier Life Span. Small dogs tend to live longer than large dogs, but even small dogs' lifespans tends to max out around 15 years or so. You can expect your yorkie to live somewhere between 12 and 15 years, with a median expectancy of 13.5 years of age.

Lifespans for popular small dog breeds: They can make an excellent companion dog, but be prepared to keep him busy and give him lots of exercise. As your boston terrier ages, however, he may begin to experience certain health problems.