Why Do Cats Like Boxes? The Science of Sitting in Cardboard

I am dictating this from inside a box. It arrived on Tuesday carrying something forgettable for the humans, and it now carries me, which is a promotion for the box. You want to know why cats sit in cardboard, and for once your species asked a question science has actually answered. There are three real reasons, all of them flattering to cats: boxes are measurably calming, your home is too cold for our refined standards, and we are ambush predators who appreciate good architecture. There is also a fourth study where cats sat in boxes that did not exist, which I will get to, because it proves our commitment to the genre.

A box is stress relief with a measured number behind it

Researchers at Utrecht University in the Netherlands tested this properly, twice, on cats newly arrived in a shelter, which is the most stressful address a cat can have. In the first study, 19 cats were split into two groups, and only one group got a hiding box. By days three and four, the cats with boxes already scored measurably calmer, and the whole box group settled as one, while the boxless group scattered from zen to frazzled. The follow-up trial ran the same idea on 23 cats and found the box group reached a stable, settled stress level by day two. The cats without a box took until day nine. Same shelter, same food, same everything. A piece of cardboard gave those cats their week back, a trick our settling-in guide already puts to work on new adopters.

Tess · Behavior desk

Quick precision before this gets framed wrong: those are two different Dutch studies. The 2014 one had 19 cats and showed lower stress scores by days three and four. The day-two-versus-day-nine result comes from the 2019 follow-up with 23 cats. And both measured the Cat-Stress-Score, a validated posture scale. Nobody drew blood for hormone tests.

Cookie · Editor-in-chief

I was about to say all of that, in fewer words, from inside the study material itself. Field research. My invoice says two studies, so that will be two servings of tuna.

Your living room is colder than you think. Ask a cat

Here is the part humans never suspect: your thermostat is set for you, and you are the wrong species. The published comfort range for cats, the thermoneutral zone, sits at roughly 86 to 100°F (30 to 38°C) per a 2016 peer-reviewed welfare review citing the National Research Council. Most homes idle around 72°F (22°C). One veterinary journal put the gap in human terms: a cat in a typical house is living the way you would at something like 46°F (8°C). Suddenly the sunbeam obsession, the radiator loyalty and the laundry-pile naps all make sense.

A small cardboard space that traps a cat's own warmth fits the same logic. You will read that cardboard is a special insulator; that one is often repeated, rarely sourced. What is sourced is simpler: we run warmer than your rooms, and small enclosed spaces help us keep it that way.

The ambush predator finally gets a proper blind

Cats are ambush hunters. Veterinary behaviorist Dr. Alison Gerken puts it plainly: cats hide until their prey passes by. A box is a hunting blind delivered free to your kitchen. Feline researcher Mikel Delgado of Purdue University describes a natural gravitation toward covered, secretive spots, and points out that indoor cats live in a world where they control very little; a box is a rare piece of territory that is entirely, unarguably ours. Danielle Gunn-Moore, professor of feline medicine at Edinburgh, traces it back further: a kitten's first experience of the world is a safe, enclosed den. To be fair to the experts, none of this comes from one single boxes-study; it is the consensus reading of people who have watched cats professionally for decades. They watched. We sat. Everyone did their job.

If I fits, I sits: cats also claim boxes that do not exist

In 2020, researchers ran a citizen-science experiment in living rooms across the world. Owners taped shapes to the floor: a real square, a visual illusion called a Kanizsa square that only suggests a square, and a control shape that suggests nothing. Over 500 households signed up; 30 cats finished all six days, and 9 of those cats ever sat in any shape at all. Those nine chose the illusory square five times and the do-nothing control zero times, and they treated the illusion about the same as the real square. The authors themselves call it a small first probe, so nobody should expect their own cat to perform floor geometry on command. Mine would not. Not because I fail illusions, but because I do not work for free.

How to serve a box properly

The professional advice on boxes is delightfully cheap. Ohio State's veterinary indoor-cat program recommends exactly the things you were about to recycle: cardboard boxes, paper bags, simple tents and cubes, somewhere the cat can retreat and feel safe without interruption, ideally with extra hiding options up high with a good view. International Cat Care's serving rule for any key resource, hiding places included, is one per cat plus one extra, in different spots around the home. The rest is table manners:

• Step 1: Leave the box where the cat already likes to be, not where it looks tidiest.
• Step 2: Remove tape, staples, handles a head could catch in, and anything scented.
• Step 3: Do not force anyone inside. A box is claimed, never assigned.
• Step 4: Rotate boxes when the novelty wears off. New box, new empire.

Zoe · Community desk

Community desk here. If your cat has claimed a box this ridiculous, we want to see it: post the photo in our community gallery and make my day.

Cookie · Editor-in-chief

Submissions will be judged on box quality, sitting technique, and whether the cat looks sufficiently unimpressed. I am the judge. The judge accepts bribes in biscuit form.

When box love is actually hiding

One honest line before the closing credits, because even a box column earns one. A cat that enjoys a box is normal; a cat that lives in one is telling you something. Gunn-Moore's warning is blunt: for a cat to be hiding all the time is really not good. International Cat Care lists hiding among the signs of a stressed cat, alongside changes in eating and grooming. So enjoy the loafing, but if the box has become a bunker, read the rest of the signals with our body language guide and the drift checklist in our cat anxiety guide, and let your vet rule on anything that has changed. Boxes are furniture, not medicine.

What to take away

• In a randomized trial of 23 shelter cats, the cats given a hiding box reached a stable stress level by day two; the cats without one took until day nine.
• An earlier study of 19 shelter cats found the box group measurably calmer by days three and four, with the whole group settling together; both studies used the validated Cat-Stress-Score posture scale.
• A cat's published comfort range is roughly 86 to 100°F (30 to 38°C), while most homes sit near 72°F (22°C), which is why cats seek sunbeams, radiators and enclosed spaces.
• The ambush-predator explanation for box love is expert consensus among veterinary behaviorists, not a single study's finding: a box works as cover, warmth and controlled territory at once.
• In the "If I fits I sits" study (published 2021), the 9 participating cats chose an illusory taped square 5 times and the control shape 0 times, treating a suggested square like a real one.
• The serving suggestion from International Cat Care: one hiding place per cat plus one extra, in different locations; a cat that hides all the time, though, is showing a stress sign worth a vet conversation.