Updated 
Sept 16th, 2018   

How old should a kitten be when it goes to a new home?

by Barbara C. French

First printed in CATS Magazine, February 2000. Reprinted with permission.

Dorie Wilkins* (*name changed to protect identity) had only been breeding Ragdolls for almost two years, and had produced her second litter. She was approached by a nice young couple who wanted a kitten, but they objected to her policy of selling kittens at twelve weeks of age. They were concerned the kitten would not bond with them. They pointed to newspaper ads advertising kittens 'ready to go' at six or eight weeks. "I let them talk me into it," sighs Wilkins. "I sold kittens at twelve weeks because that's what everyone else seemed to be doing. I didn't really know why." She relented and let one of the kittens go to its new home at seven weeks of age.

The kitten was returned at ten weeks, weighing less than it had when it had gone to its new home three weeks before. The owners complained that the kitten had the sniffles and chronic diarrhea and wasn't using the litter box. It hadn't settled in with their resident cat, and the kitten spent much of its time hiding under the couch. "They said they'd never get a purebred cat again, because obviously they're not healthy," Wilkins relates. With veterinary care and a lot of TLC, the kitten was back on its paws in a few weeks. Wilkins waited until this kitten was almost six months old before placing it again.

The kitten's problems had nothing to do with its heritage.

"Kittens should leave their homes at a minimum age of twelve weeks," says Dr. Betsy Arnold, DVM, a veteran Siamese breeder and veterinarian with an all-feline practice in Rochester, New York called Caring for Cats. "In my practice I have seen kittens coming in at six and seven weeks who weight twelve, maybe fourteen ounces. These are infants. They needed to stay with their mothers."

Twelve weeks may seem old to people accustomed to seeing newspaper ads advertising kittens who are "ready to go" at six or eight weeks of age. Most of us who have had cats have acquired kittens that young. They are cute at that age, and most people enjoy having such young kittens to watch them grow. However, we may permanently harm kittens by separating them from their mothers so early. There are crucial mental, emotional, and developmental milestones that a kitten experiences between six and twelve weeks of age. Separating the kitten from mother, siblings, and familiar surroundings at that age can cause undue anxiety and stress at the least, and serious medical problems or even death in the very worst cases.

Problems with immunity and health

"One of my main concerns with early separation is that kittens' immune systems are really developing between eight and twelve weeks of age," says Dr. Arnold. "The immunity from their mother is wearing off, and the immunity from vaccination is just starting to take over. During this time, they are more susceptible to illness, such as upper-respiratory problems and diarrhea." Kittens generally receive vaccinations against panleukopenia, rhinotracheitis, and calici viruses (commonly called the "distemper combination" shot) at six, nine, and twelve weeks of age. However, immunity from vaccination does not happen immediately; shots can take up to ten days to be effective. Up until this time, kittens receive some measure of immunity through antibodies from their mother's milk, but this is also the age where they are beginning to wean. Their immune system "kicks over" from immunity from mother's milk to immunity from vaccination. During this time, their immune system is busy with this task, leaving the kitten less able to fight off other illnesses. "The stress of going to a new home and being exposed to different germs can make the kitten more susceptible to illness during this time," adds Dr. Arnold.

At six or seven weeks, a kitten has only received his or her first shot series; the new owner must remember to give the second boosters. Sometimes they forget, and this can have disastrous results. Himalayan and Persian breeder Barbara Redalia of Tuleburg Cattery recalls, " Once a pet purchaser bought a kitten from us, neglected to give it the second vaccination, and when their son became allergic, returned the cat to us. Unfortunately the cat had contracted rhinotracheitis at their home and exposed a pregnant cat to this virus at our house. This cat, whose own immunity to rhinotracheitis was apparently waning, became extremely ill, miscarried her litter, and was eventually euthanized."

"I have spoken to many new pet owners who have purchased their kittens at eight weeks of age, which is the minimum legal age in Florida," says Susan Geren, who breeds Persians and Himalayans under the cattery name Pyewacket. "The overwhelming majority of them had health problems with their new babies, probably caused by the stress of being separated from their siblings and mother at such an early age. I have explained to them my reasons for not placing my kittens early and suggested that in the future they use this as a gauge to ascertain which breeders are more interested in the income provided by kitten sales than they are in placing healthy, well adjusted kittens. It is most definitely more expensive to keep kittens until they are four to five months old."

Some studies have shown that vaccination at six weeks might be too early. "I once lost a 10-month-old cat to panleukopenia (feline distemper)," recounts Mary Tyson of Thaison Siamese. "After long discussions between the vaccine manufacturer and my vet, Pittman Moore's research head concluded that it was not a bad batch of vaccine. Cornell [Feline Health Center], which had done the post mortem analysis (and also analyzed blood samples taken while the cat was still alive), concluded in conjunction with Pittman Moore that some cats do not develop lasting immunity from vaccines administered earlier than 16 weeks of age, and this cat had had his last shots at 12 weeks. Thereafter I maintained a policy of not letting kittens leave home until they had had their shots at 16 weeks old." "The most important reason I place kittens at 12 weeks of age (or older) is because kittens can be extremely fragile, and putting them in a new home and environment puts additional stress on them, upping the chances of getting sick," says Burmese breeder Jaina Wendtland. "When this happens the kitten buyer blames the seller, and rightly so in many cases."

When a kitten is ready to leave may also vary from cat to cat, or from breed to breed. Some cats are simply not big enough to go on their own until they are a bit older. Devon Rex breeder Carole Goodwin notes that cats of her breed are small and need a full twelve weeks to mature and socialize. Amanda Bright, who breeds Russian Blues under the cattery names of Kyina and Talisker, notes that her breed tends to be slender and she feels the cats need more body mass to handle vaccinations. She feels it is wiser to vaccinate them a bit later so that the cats can better handle problems if they occur.

From a health standpoint, it is best to allow the kitten to receive its entire first shot series, including boosters, while at home in familiar surroundings. First shots are not enough to confer immunity, and the kitten needs time for its immune system to change over completely from one system (mother's milk) to another (vaccination). They should also be of a sufficient size and physical maturity before they are ready.

Problems with eating and eliminating

"Weaning isn't an event; it's a process," says Dr. Arnold. "They don't just start eating food one day. They eat a little food, nurse, eat a little, nurse, and so on. Eventually they eat more than they nurse, and then stop nursing altogether. This doesn't happen by six or eight weeks of age."

Left to their own devices, mothers will eventually stop allowing kittens to nurse. With most cats this occurs naturally anywhere from eight to twelve weeks. However, this process is very important, as it teaches the kitten to learn to deal positively with frustration and denial. As the mother starts refusing to allow the kitten to nurse, which the kitten very much wants to do, she teaches the kitten how to cope with that frustration. Kittens who do not learn this lesson may develop behavioral problems.

Weaning is not simply a matter of getting a kitten to eat solid food. It's an important time when the kitten begins to assert its independence from its mother. This needs to be a gradual process. "For the most part, my babies still nurse at 9 and 10 weeks, and sometime beyond," says Rosi Carroll of Bengals by RoJon. "I have never had a customer call me up after picking up one of my kittens, complaining about the kitten meowing for its mother. They settle right in to their new environment."

It's also common for too-young kittens to eat poorly and have litter box problems. Many kittens at age six to eight weeks aren't consistently using the litter box. I have found that my own kittens can take up to ten weeks to have litter box habits down pat. And diarrhea can accompany the changes in diet and stress that come with a new home. Diarrhea can be life-threatening to a small kitten; severe dehydration and rapid weight loss is a serious problem when one has so little body mass to start.

Problems with socialization and behavior

People often express a desire to have a younger kitten because they are afraid the kitten will not bond with them once older. This is simply not true. As Ann Segrest of Kiriki Korats says, "The older kittens bond with their new humans just fine. Cats do not have, nor do they need to establish their place in the "pack" like dogs must do. This is the myth that must be dispelled so that kittens will have the opportunity to learn from their mothers and be as healthy and stress-free as possible when they go to their new homes."

It is true that kittens who are separated at a young age from their mothers will often bond to a person as a surrogate mother. This may seem cute, but it's unhealthy. Such kittens will often suck on blankets, clothing, buttons, even earlobes or on themselves. They may become dependent upon humans to the point that they become fearful or neurotic when left alone. Many hide or run at the sight of unknown people. Most commonly, however, cats who are deprived of proper socialization don't learn how to be with other cats. This makes them especially inappropriate as house pets in a multicat household.

The kitten socialization phase starts at about four weeks of age and can continue until up to fourteen weeks old. Kittens learn to explore their world through this period, under the comforting guidance of their mother. Between nine and fourteen weeks old, they learn from their mother and siblings how to interact with other cats. They learn how to recognize and interpret cat body language. Quite literally, a cat who misses out on this important social step may not learn how to "talk" to other cats.

It's also during this time when the kitten needs to be exposed to variety of people in a positive way so that it doesn't become afraid of different types of people. Improper early socialization is why some cats seem to be afraid of men, or of people with glasses, or other odd quirks.

Manx breeder Marj Baker was faced with having to raise three kittens whose mother had become unable to care for them when they were three weeks old. "[These kittens] were biters - well, actually just nibblers; they wanted to chew on my fingers -- and wanted my full attention all the time. The also loved my hair to chew on and any item of clothing that was mine got licked and chewed. They seemed very mouth oriented and were very unhappy if left alone by themselves. Most Manx are happy to entertain themselves most of the time but not these three. They also were harder to [train to use a litter box], finding the floor a convenient place to squat. I guess I was not a very good mom cat."

Deborah Feldham of Glendoveer's Abyssinians had a similar story. "In one instance I took in two orphaned kittens that I had to syringe feed because they were so young," she says. "They were not easy kittens to work with. They were jealous and insecure, often showing their insecurities by going to the bathroom in inappropriate places and scratching or hissing at strangers. I believe that if these kittens had been born in a more secure environment and raised with their mother [to an older age], they would have been better prepared, emotionally, to fit into their new homes. Kittens learn from mothers, litter mates and their surroundings."

Kittens need the time with their mothers and siblings to learn important life lessons - lessons that will make them happy, healthy, confident kittens. "I have seen kittens taken from their mother too young become cloth chewers and neurotic," says June Abbott Colwell of Velpaws Siamese. "[Kittens] not only need to be with their mothers, but also with their siblings. They learn proper acceptable play behavior from both mother and siblings. Kittens taken away too young are not as tolerant or as sure of themselves as older kittens."

t twelve weeks of age, most kittens are weaned or nearly fully so, have had adequate socialization with mother and siblings, have received their full series of kitten shots, and have gotten through the critical immune system "kick-over" period. Properly handled and socialized by people, these kittens have learned to explore their world and will meet it with a happy, outgoing confidence that will carry them throughout their lifetime. This may vary from cat to cat, or breed to breed.