Your New Pet’s First Month: The 3-3-3 Rule and Beyond

Now that your new pet is home, it’s time to focus on settling in. Getting to know each other at home can be a fun and sometimes tricky few weeks, so we’ve put together a guide to help it go as smoothly as possible, from the moment you walk them through the front door up until the months after, when you can’t remember life without them. Here is what you need to know about setting the family up for success, including the 3-3-3 rule, the car ride home, and introductions to other family members.  

Pick a “Settling-In” Spot

So as not to overwhelm your new best friend, it’s important to go slowly once you are home and pick a “settling in” spot that will allow them to get acclimated. Introducing them one room at a time to your house can be a calm and gentle way for them to get their bearings, especially if there are other animals in the house or small children.  

Set up their bed and/or crate to let them know it’s a safe space by placing soft blankets in it, but also be flexible to them having a preference elsewhere once they have the lay of the land, i.e., a sunny spot or a cool spot. Consider limiting the number of visitors in the first few days, particularly for cats.  

Schedule a Vet Visit

Your new best friend’s new best friend (besides you!) will be your vet. Try to schedule a vet visit within the first week of bringing home your new cat or dog so they can get up to speed on your pet’s general health and any concerns you might have. This is where you can discuss things like spaying or neutering, vaccine schedules, food, flea, tick, and heartworm prevention, and more. The vet will do a general well visit to examine every inch of your pet and advise you on a schedule for future well visits going forward.  

Choose the Right Pet Food

Your vet can also recommend appropriate food types for your cat or dog’s age and lifestyle. For example, kittens and puppies need more calories as they grow, and senior dogs might need a few extra nutrients to support joint health. Your vet can also advise you on how much to feed your pet depending on their weight and activity level.  

Update Your Calendar & Routine

A new pet means a lifestyle change, even if they’re a cute couch potato. You’ll want to update your routine to make sure they have plenty of enrichment and exercise time, plus potty breaks for dogs and regular cat litter box cleaning regimens for you. Start slow when leaving them alone and consider shifting your activities around their comfort levels. Create a grooming schedule for at-home maintenance or reach out to a professional groomer if your breed could benefit from an expert’s help. Be sure to schedule plenty of time to snuggle and get to know each other, too. 

The 3-3-3 Rule for Pets  

The 3-3-3 Rule is a guideline of what to do in the first three days, three weeks, and three months to set you and your new pet up for success. 

What Is The 3-3-3 Rule? Your New Pet’s Adjustment Timeline Explained

The 3-3-3 rule is a handy way to remember a general timeline for a new pet to feel fully at ease. It outlines how the first three days, first three weeks, and first three months should go with your new pet, keeping in mind that every four-legged friend is different and this is just a guideline.

The 3-3-3 Rule for Dogs

To set your dog up for success, here is the 3-3-3 rule for dogs, although every animal is unique:  

Three days for a dog to adjust to their new environment. This can be the most confusing time for them, but don’t give up! They could show signs of anxiety, shut down completely, refuse to eat, or act out. Keeping a routine and going slowly and gently with them will get them to settle in.

Three weeks for them to settle into your family’s rhythms. After three weeks, a new dog should feel comfortable with your routine, although they might still feel a little disoriented. If you have a rescue dog, it might take a little longer to adjust, and they might exhibit undesirable behaviors, such as getting into things they shouldn’t be into, as they begin to feel more comfortable.

Three months to feel at home. It could take up to three months for them to fully relax and begin to show their real personality. This is also the time when some behavioral issues might pop up that need to be addressed as their comfort level around you becomes higher. Within three months of an established routine and good boundaries, your dog should understand the house rules and behave like a member of the family.

The 3-3-3 Rule for Cats

To set your cat up for success, here is the 3-3-3 rule for cats, with the understanding that cats often operate on their own timelines:  

Three days for a cat to adjust to their new environment. For cats in particular, it’s important to hold them to physical boundaries and not give them complete access to your home in the first few days. Try introducing them room by room to prevent them from becoming overwhelmed, and limit visitors during this time. Be sure to keep the litter box accessible to them during this transition.

Three weeks for them to settle into your family’s rhythms. After three weeks, your new cat should be able to feel confident enough to roam freely if you permit them, although cats that have experienced trauma might need more time.

Three months for them to feel at home. Within three months, your cat should be able to fully relax, understand house rules, and act like a member of your family. 

Your First 48 Hours Together: Bringing Home a New Pet

There’s no feeling like taking a new friend home to show them their new digs. Here’s what to expect over the first 48 hours with your pet.  

The Car Ride Home

As much as you might want to cuddle your new friend on the drive home, it’s important that they are safely secured in your car for the trip home. Pets should always ride in the back seat as airbags could injure them if deployed. For dogs in cars, the safest place is a size-appropriate crate that is locked and anchored in the car. Locked crates can also prevent a dog from bolting if a door or window is open.  

Adult and senior cats might show more genuine fear in the car than dogs, as most of their car time is likely to vet visits. Cats in cars should also be in a locked or zippered size-appropriate crate in the back seat. If possible, let the cat explore the carrier at the shelter or at their former home to familiarize themselves and possibly reduce their anxiety.  

Feeding Your New Pet

Food continuity matters for dogs and cats in the first 48 hours. If possible, try not to do any switching until after you’ve been to the vet. Moving too fast through a food transition can be hard on cats’ and dogs’ stomachs, and it can stress them out. Puppies and kittens are especially vulnerable to upset as their digestive systems are still developing. Your vet can advise you on dry food, wet food, kitten and puppy food, senior dog and senior cat food, breed-specific food, therapeutic food, and more. They can also help you with food amounts, spoilage pointers, and hydration tips.  

After you get approval from your vet, you can start a food transition if they advise doing so. Go slowly, and tell your vet if there are any issues ASAP. If your dog or cat refuses to eat within the first 48 hours of being home, call your vet.  

First Day Do’s and Don’ts

You might have an instinct to set up your cat or dog and start calling friends to come see how adorable they are. However, there are some do’s and don’ts to keep in mind to make sure that your pet is going to thrive. They include:

Do’s

• Do keep them confined to one settling-in space to help them get acclimated. Put your cat’s litter box in this confined space.  
• Do let them exit the crate or carrier on their own terms.  
• Do let them approach you.  
• Do offer water.  
• Do keep feeding them the same food they ate before if possible, even if you want to switch.  
• Do keep things as quiet and calm as possible.  
• Do let them come to you to initiate interaction. Kittens and puppies will be more open than older dogs or cats might be. Give it time and be patient.  
• Do take your dog outside frequently, even if they are housebroken.  
• Do plan for accidents, no matter how old your pet is, and be sure to reward them for positive bathroom habits.  
• Do put on their collar and/or ID tag ASAP.
• Do stick to a schedule and routine to help them adjust to the household.  

Don’ts

• Don’t let them go everywhere immediately. Keep them confined in the first few days so as not to overwhelm them, and gradually introduce them to new spaces.  
• Don’t change their food within the first 48 hours, if possible.
• Don’t invite too many new faces to visit.  
• Don’t force attention or handle them if they don’t seem to want the attention.  
• Don’t leave them unsupervised in spaces that haven’t been pet proofed.
• Don’t introduce them to small children or other pets on day one. They need a bit of time to decompress.  
• Don’t correct or scold them if they have an accident.  
• Don’t take them to places where there might be too much stimulation, like pet stores.  
• Don’t leave them alone for long periods of time.  

Introducing Your New Pet to Other Pets

Some pets thrive in environments with other pets, but some don’t. Introducing your new pet to other four-legged members of the family should be a slow and gentle process so that everyone feels comfortable.  

Introducing New Dogs to Other Dogs  

It can be helpful to have the dogs on a short leash as they are introduced. This way, owners are in control. If possible, introduce dogs to other dogs outside on neutral territory so they can sniff each other. You can work your way up to them being around each other inside.  

Introducing New Cats to Other Cats

Cats can be territorial, so cat-to-cat introductions should go especially slowly. Start by mixing scents a few days before, letting both cats explore each other’s scents. The new cat should be confined to a room, and established cats can smell them through the door. Next, let the new cat begin to explore the house room by room. The goal is to desensitize the cats to each other’s scents. Once they seem relaxed, they can lay eyes on each other, with the new cat in a carrier. Then, you can let them move on to being physically around each other.  

Introducing Cats and Dogs  

Introducing cats and dogs takes a bit of skill. Swapping scents can help make them more comfortable with each other, and being able to see each other without touching, such as through a baby gate or glass door, can make the first glance easier. The first face-to-face introduction should have the dog on a short leash so that you are in control of the situation, and make sure that the cat has access to vertical space a dog can’t reach to retreat if necessary. Keep them separate or supervised until everyone seems relaxed.  

Introducing Your New Pet to Kids

Your kids are likely very excited about a new family member coming home, but it’s important to get everyone comfortable with the new situation. Go slow, and introduce dogs on a short leash if the kids are older or through a baby gate if they are little. Keep treats with you to have the pet make a positive association with the kids. Model gentle touch with young children, and encourage them to pet your animal in safe areas. Toddlers are chaotic, and their quick movements can make pets anxious, so pay particular attention when making introductions. Provide clear instructions to older kids about approaching your new pet and help them understand behaviors that might indicate that the pet needs a little breathing room.  

Keep in mind when researching a new pet that some breeds aren’t as easygoing with kids as others, but no dogs or cats, regardless of age, should be left alone with children in the room. 

The First Month: Building Confidence Together

Don’t fret if your first few days or first week haven’t gone perfectly. Your pet is still adjusting to their new life and there are bound to be some bumps in the road. The first month is all about building confidence together as a family unit and laying the groundwork for long-term success.  

Establishing Routines (Without Being Rigid)

One of the most important things you can do for your dog or cat is to establish a routine and stick to it as much as possible. There are of course going to be days where things might be a little off, but the more a pet knows what to expect, the calmer and more confident they will be. Predictable feeding times, potty times for dogs, play times, and sleep can help them understand how the day will go and lead to happier, more confident animals.  

Starting Training & Socialization

Socialization is a hugely important part of having a pet, especially a puppy or kitten, as they learn by repeated positive exposure. Gently and slowly introduce your pet to different places, people, sounds, and environments so that they feel comfortable early on. Bring treats and toys so that the pet makes positive associations with the new place or experience. For puppies, learning how to walk on a leash with manners, obedience, and more can be taught through positive reinforcement training. Cats can be trained via positive reinforcement training as well. Older dogs and cats will have established behaviors, so try to meet them where they are without expectations. Consistency matters for all ages and stages.  

When to Call the Vet vs. When to Wait It Out

You already have learned to call the vet within the first week of bringing your new friend home to get them checked out and discuss issues and preventive care. After that, it can be hard if you are a first-time pet parent to know what kinds of things warrant a call to a vet. Here’s a short list of a few things that can be hard to figure out in the first few weeks together. When in doubt, it’s always safest to call poison control or your vet, or head to your local emergency room. 

Bringing home a new cat or dog, no matter what life stage, breed, or personality, is an exciting milestone for both you and your pet. By using the 3-3-3 rule as a guideline, you can set both of you up for success and ensure that you have a good foundation on which to build your forever relationship. Check out our Ultimate Adoption Checklist for more tips.