April 2, 2026, 6:28 am | Read time: 6 minutes
A new home is a big adjustment for any cat—whether young or old, shy or curious. How quickly they settle in depends on many factors. The so-called 3-3-3 rule helps better understand and ease the acclimation process for cats. PETBOOK editor Louisa Stoeffler has already acclimated several rescue animals and knows why patience, consideration, and structure are so crucial in the first 90 days.
3-3-3 Rule for Cats as a Useful Guide
A new home is a big adjustment for any cat—and how quickly they settle in can vary greatly. From my previous experiences acclimating rescue animals, I know that not every cat goes through the 3-3-3 rule in the same way. Some animals—like my cat Remo—showed a high level of curiosity within minutes and began exploring the entire apartment. Although he had just arrived from Spain, he couldn’t wait to get out of his carrier and claim the whole apartment—and me—as his own.
Others, like my cat Minka, need significantly more time and initially benefit from a clearly defined, safe space. With her, I also followed the rule beyond the apartment after a move: She stayed indoors until she was fully settled. Only then did I gradually let her outside, allowing her to take short trips and safely explore her new territory.
These differences highlight that the 3-3-3 rule is very useful, especially for acclimating cats that still need to build trust or struggle with changes after moving. It serves as a guide and should always be adapted to the individual character of the cat. This rule of thumb also indicates when it might be advisable to consult a cat expert if acclimation isn’t progressing. Patience, consideration, and a well-structured environment are crucial to making the start of a new life as stress-free as possible.
The First Three Days – Retreat and Orientation
Right after moving in, cats need one thing above all: peace. New smells, unfamiliar people, unknown spaces—all of this can be overwhelming. Many cats retreat in the first few days, hide, eat or drink little, and appear uncertain. Others, like Remo, initially take a big tour of the apartment, sniff everything, but then retreat to a safe place to sleep.
It’s important to give the animals exactly the time and space they need during this phase. Don’t be discouraged if you hardly see the cat in the first few days. They are in an unfamiliar environment and may be very nervous. During this initial period, you often see little of the animal’s true character.
By giving the cat their space, you show them that their new environment is safe, and they gain a sense of control over the situation. After a few days, the cat can then decide for themselves to make the first contact, the mutual “sniffing.”
Setting Up a Retreat
A prepared retreat also helps with acclimation. This includes food and water bowls and at least one clean litter box. Start with a small area that your cat can explore. Even if the new roommate seems very friendly, it’s wise to keep them in a confined space initially.
My cat Remo has also been through a move. I made sure he could settle in a quiet room with familiar scents around him. As long as work was still being done in the apartment, he retreated to his litter box. But as soon as it got quiet in the evening, he wanted to explore the other rooms again. Still, it can be helpful to keep cats in one room for the first three days.
In this phase, the following reactions are quite normal:
- Overwhelm
- Hiding or retreating
- Reduced appetite
- Uncertainty
- Testing boundaries
Three Weeks – First Routines and Growing Trust
After about three weeks, the cat has likely gotten used to their owner’s daily routine. They recognize feeding times, which is why it’s important to establish times during acclimation that can be easily implemented in everyday life. The animal becomes more familiar with the spaces and slowly begins to move around the entire home. It’s helpful if familiar items like blankets, scratching posts, or litter boxes are available in multiple locations. This way, the cat feels safe everywhere. Some animals have already discovered the whole house for themselves, while others prefer to stay in their familiar space.
If you want to establish outdoor access, now is also the time to create small spaces for it. This should be done in a calm setting, ideally in a quiet backyard or garden, so the cat can explore this part of their territory in a small setting.
Now is also the right time to find a veterinary practice you and your cat trust and to get them used to small checks of eyes, nose, ears, and claws with medical training. The carrier should also be used here so the cat sees it as a normal place and not a source of fear. With a soft blanket, it can become a substitute cat cave where the animal feels comfortable.
Typical developments in this phase:
- The cat becomes more trusting
- The daily routine is recognizable
- They explore more rooms
- First behavioral peculiarities may become visible
- Their personality becomes more apparent
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Three Months – Settled and Ready for Bonding
After about three months, it’s usually the case: The cat truly feels at home. Trust has grown, and a stable bond can form. Now begins the phase where shared rituals and even initial training attempts are worthwhile, and stable bonds can be built that can be maintained throughout the cat’s life. The effort of the past weeks is now paying off, the cat is entirely themselves and probably already comes to cuddle or sits ready when it’s time for brushing or a play session.
If the cat hasn’t yet responded to their name, now is a good opportunity to train them. Calling can happen throughout the day, but you should confirm each response with a treat, so it’s worth always having some in your pocket. Important: Proceed at a pace that is comfortable for your cat—positive reinforcement is key.
After three months, it usually shows:
- The cat feels safe and settled
- They trust their humans
- Routines are established
- The bond grows
Conclusion: Patience is the Key to Cat Friendship
The 3-3-3 rule offers valuable guidance for anyone looking to give a cat a new home. Each phase—from cautious getting to know each other to a familiar bond—requires time, understanding, and consideration. Those who respect these phases create an excellent foundation for harmonious living with a happy cat.