On our ratings the Rat Terrier comes out ahead wherever the two differ, and for most families that is the right call. The Jack Russell's case is drive: it suits an owner who wants a small dog that never runs out of steam.
- Drive. The Jack Russell goes back to the Reverend John Russell, a 19th-century Devon parson who wanted a terrier to run all day with his foxhounds and then bolt the fox from its earth. It still has more stamina and persistence than most owners expect, and without a daily job it digs, escapes and barks. For agility, flyball, earthdog tests or long hikes, that is the point. The Rat Terrier, an American farm dog bred to clear barns of rats, is just as quick, but the AKC calls it "one of the calmest of the terrier breeds" and "extremely intelligent and trainable", and rates it higher with young children. Neither is an easy first dog; the Rat Terrier is the safer bet.
- Look. A Jack Russell is mostly white with tan or black markings, has button or dropped ears and a smooth, broken or rough coat. A Rat Terrier is always smooth-coated and pied, with large patches of black, chocolate, red, apricot, blue or lemon on white, and its ears may stand erect. A hairless line of Rat Terriers became a breed of its own, the American Hairless Terrier.
- Size. The AKC, which registers the Jack Russell as the Russell Terrier, gives one size: 10-12 in and 9-15 lbs (dogs registered with the Jack Russell Terrier Club of America may be 10-15 in). The Rat Terrier comes as a Miniature at 10-13 in or a Standard up to 18 in, within one weight range of 10-25 lbs, so ask which size the parents are.
- Barking and small pets. Both are alert barkers. Both were bred to hunt small animals, the Rat Terrier to kill rats, so hamsters, rats, rabbits and pet birds are at risk with either. Off-leash running belongs in fenced areas.
- Health. Both live long: 12-14 years for the Jack Russell, 12-18 for the Rat Terrier. With either breed, ask for both parents' DNA test for primary lens luxation (PLL), an inherited eye disease, and a kneecap check; for a Jack Russell, also a BAER hearing test and an eye exam; for a Rat Terrier, hip and heart results.
- Price. The Jack Russell is cheaper to buy: about $500-$1,500 for a puppy, against $900-$1,600 for a Rat Terrier.
Pick the Jack Russell if you are an experienced, active owner who wants a tireless partner for dog sports and can live with digging and barking; pick the Rat Terrier for a family dog with the same terrier spirit that is calmer and easier to train.