A dog's first 72 hours in a new home

Quick answer

This is week three, not day one. The first days are about safety and sleep, not about seeing the dog's real personality.

The first three days are not about bonding, training or showing the dog around. They are about two things: not losing the dog, and letting it sleep.

A newly rehomed dog is running on stress hormones that take days to fall. What you see in the first 72 hours, in either direction, is not the dog you have adopted.

• Fit ID with your phone number before the dog leaves the car, and transfer the microchip registration into your name the same day.
• Use a properly fitted harness and a second point of attachment. A frightened dog reverses out of a flat collar in seconds.
• Keep the previous food for at least the first week, then change it gradually.
• Expect no appetite, loose stool, and either flat sleeping or restless pacing. All are normal at this stage.
• Set the household rules from day one, because the dog you meet in week three is the one you will live with.

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The highest risk in the first 72 hours is escape, and the commonest escape is through a front door or a garden gap in the first hours.

A dog that has not yet formed any attachment to you will not come back when called, and a panicked dog crosses roads. Before the dog enters the house: check the garden fence line at ground level for gaps, check gate latches, agree who opens the front door and how, and decide that the dog is on a lead every time an external door is used. Ex-street dogs and dogs from overseas rescue are far higher risk and should be double-secured on a harness and a martingale collar with the lead clipped to both.
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Decide in 60 seconds

Why the first three days look nothing like the dog you adopted

Rehoming is a total sensory and social reset. The dog has lost its people, its smells, its routine and its map of where things are, and it has no way of knowing this arrangement is permanent.

Physiologically, cortisol rises and stays raised for days after a dog changes home. That has practical consequences: a dog with high circulating stress hormone eats less, has looser stools, sleeps badly or excessively, startles more easily, learns poorly, and has a lower threshold for growling and biting than the same dog will have in a month.

Two opposite presentations are both common.

The shut-down dog. Quiet, undemanding, does not explore, does not play, follows quietly, seems remarkably well behaved. Owners describe this as "he settled straight away". It is usually the opposite: the dog has switched off. When it comes back online in week two or three, new behaviours appear and owners believe the dog has changed.

The overwhelmed dog. Pacing, panting, unable to lie down, whining, unable to sleep, mouthing, jumping. This dog is not "high energy" and does not need a longer walk. It needs less input, not more.

The popular version of this is the "three days, three weeks, three months" rule. The core idea is sound, and the failure mode is real: owners use it to excuse waiting on things that need a vet, and to postpone setting household rules until the dog "settles", which then means changing the rules on an animal that has just learned them.

Treat the timeline as a description of how confidence returns, not as permission to wait on a medical sign or to be inconsistent.

Before the dog comes through the door

Everything set up before arrival: a bed in a low-traffic corner, a crate with the door fixed open, two bowls, and the lead that goes on before any door opens.

The arrival hour

Drive home calmly and go straight to the garden or a quiet patch of grass, on lead. Let the dog toilet and sniff for as long as it wants. This is not a walk.

Bring the dog in on lead, let it drift through the ground floor without following it around, then drop the lead and let it choose where to be.

Do not give a tour, do not call it, do not offer toys, and do not photograph it in everyone's arms.

Show it where water is. Offer a small meal of the food it is used to, and take the bowl away without comment if it is not eaten.

Then leave it alone. The single most useful thing you can do in the first hours is be boring.

No visitors. Not for the first few days, and preferably not for a week. The dog cannot tell friends from strangers and has nowhere it knows is safe.

Children need rules before, not after. No approaching the bed or crate, no hugging, no faces near the dog's face, no taking anything from it, no following it when it moves away. Every interaction supervised, no exceptions.

Resident dogs. Do not introduce inside the house on arrival. Walk them in parallel on neutral ground first, at a distance, then let them share space with a baby gate between them, then together for short periods. Feed them apart. Pick up all the toys and chews for the first week, because resource conflict is the commonest cause of a first fight.

Resident cats. The cat needs an escape route and high places the dog cannot reach, and the dog needs a gate it cannot pass. Do not "let them meet".

The first three days, hour by hour

Sleep is the priority. A dog coming out of kennels is often profoundly sleep deprived, because kennels are noisy and lit. Expect a lot of sleep, and protect it. Do not wake a sleeping dog, do not let children near a sleeping dog, and do not fill the day with activity.

Toilet routine. Take the dog out on lead first thing, after every meal, after every nap, and last thing at night. Stand still and quiet, reward the moment the dog finishes, and go back in. Assume no house training regardless of what you were told: a dog trained in another home has no idea how to ask you.

Food. Same food, same amounts, split into two or more meals. Do not change the diet in the first week even if the food is not what you would have chosen. If the dog eats nothing on day one, that is normal. If it has eaten nothing by 48 hours, ring the vet.

Water. Always available. Drinking far more than expected is worth noting, because it can be stress, but it can also be a sign of illness in a dog with an unknown history.

Exercise. Short lead walks in quiet places, or none at all on day one. A long walk or a dog park is the classic first-week mistake: it floods an already overloaded dog and produces reactivity that then looks like the dog's temperament.

Alone time. From day two, leave the house for two minutes, then five, then fifteen. This matters. A dog that has company continuously for two weeks and is then left for a working day is being set up for separation distress.

Night. Put the bed where you will be. If the dog cries in a distant kitchen, move it to your bedroom and move it out gradually over weeks. This is not indulgence, it is avoiding two weeks of broken sleep and a learned association between night and panic.

What is normal, and what is not

Kennel cough is worth expecting. The incubation period means a dog that leaves a kennel healthy often starts coughing a few days later, at home. It sounds dramatic, like something stuck in the throat. Most dogs remain bright and it resolves, but it is contagious, so keep the dog away from other dogs and ring the practice before walking into a full waiting room.

Parvovirus is the puppy emergency. A puppy with an unknown or incomplete vaccination history, vomiting and passing bloody diarrhoea, is an emergency and needs to be seen the same hour. Do not wait to see if it improves, and warn the practice before you arrive so they can isolate.

Bloat is the deep-chested emergency. Retching that produces nothing, restlessness, drooling, and a belly that looks larger or tighter. Stress plus fast eating plus a large chest is the combination. This is a surgical emergency measured in hours.

What belongs to week two, not day one

This is the destination, not the starting point. Mouth, ear and paw handling is built later, in short paid sessions, once the dog trusts the household.

Do not do any of these in the first 72 hours, and start them once the dog is eating, sleeping and toileting normally:

Handling work. Touching ears, feet and mouth, and eventually tooth brushing and nail trims. Build it as cooperative care with food, in seconds not minutes. Grabbing a new dog's mouth is a fast route to a defensive bite.

Grooming, bathing and the groomer. A bath on arrival is a common impulse and a bad one unless the dog is soiled.

Training classes and dog parks. Both are heavy social environments.

Meeting the extended family and the neighbours.

Changing the food.

Any behaviour modification for barking, pulling or reactivity. You cannot assess these yet.

What changes with age, breed and background

Puppies. Vaccination status decides where they can go. Toilet breaks are far more frequent, they need sleep in far larger quantities than owners expect, and the socialisation window is running, so quality exposure at low intensity matters even in the first week. Do not let a puppy do stairs repeatedly or jump off furniture.

Adolescents. The most commonly returned age group. Expect testing of every boundary from around week two onwards, and set the rules now so you are not changing them then.

Seniors. Slippery floors are a real hazard for a dog with hind-limb weakness or arthritis, so put down runners on the routes it uses. Expect night waking and possible toileting accidents. Sensory loss means the dog may not hear you approach, so wake it by voice from a distance, never by touch.

Brachycephalic breeds. Stress and heat both cause airway distress in flat-faced dogs. Noisy breathing, blue-tinged gums or collapse is an emergency. Never leave one in a warm car, not even briefly, and keep the first days cool and quiet.

Working and herding breeds. They do not need more exercise in the first days, they need less input. Chronic over-arousal in the first weeks is what produces the spinning, chasing and nipping that owners later call a training problem.

Ex-street dogs and overseas rescues. Assume a very high flight risk, assume no house training, assume unfamiliarity with stairs, doors, cars and floors, and use double-secured equipment for months, not days.

Dogs from a home rather than a kennel. Often settle faster, but grieve more visibly. Loss of a previous owner is real and shows as searching, waiting by doors and refusing food.

What the vet will want at the first appointment

Book a wellness exam within the first week, sooner if anything is wrong.

Ask about a faecal sample if the stool is loose, about kennel cough if there is any cough, and about parasite treatment, because worming and flea status from a rehoming source is often unclear.

When to get help

The realistic target for day three: a dog that lies down on its own bed, in its own time, without being asked.

Go immediately for repeated unproductive retching with a distending abdomen, bloody or black diarrhoea, vomiting in a puppy, breathing difficulty or noisy laboured breathing, collapse, pale or blue gums, or a suspected poisoning.

Contact the practice the same day for a cough, no food or water in 48 hours, no urine in 24 hours, diarrhoea beyond 48 hours, obvious lameness, or any dog that seems painful.

Contact a qualified, force-free behaviourist within the first week if the dog growls or snaps when approached, guards food, resources or a resting place, cannot be left alone at all, or panics at handling. These are all far easier to change in the first month than in the sixth.

And if the first three days have gone badly, that is normal too. Almost nothing you see this week is the dog's settled behaviour, and almost nothing you see this week needs to be solved this week.