Should indoor cats be allowed outside?
If you ask my neighbor across the street, yes. All 11 of them. Growing up in close proximity to the country, the answer was a resounding yes. All of our household cats spent their lives outside, for better and, often, for worse.
But anecdotes about whether or not cats can be outside are just that—anecdotal. Everyone and their neighbor seems to have a strong opinion one way or another about whether cats should be allowed out.
This is when it can be helpful to look at some data to make better decisions.
Can indoor cats go outside?
Technically, yes. Cats can go outside. (There's my one dad joke for this post.)
Jokes aside, I've unearthed a few pretty good studies about outdoor access for cats. One revolves around the demographics and lifestyle behind the owners making this decision, and another includes an assessment of risks and benefits.
I'll be referring to them alongside other studies where it makes sense, but I can't say conclusively that they were well-run (I'm no Emily Oster).
Typically, this topic breaks down into three camps. The first two are the most common:
We'll get into all three and the pros and cons of each.
The case for indoor-only cats
While in New Zealand, my husband and I heard a lot about a local menace at large: the common house cat.
Warnings about the fuzzy hunters cropped up on brochures, billboards, and even in a surprise lecture on a rope climbing course. House cats have been sharply decimating the local bird population.
But why do we actually decide to keep our cats inside, globally? Is it to save local birds, or is it something else?
The #1 reason we choose to keep our cats inside is road traffic concerns.
This is a compelling reason. Some researchers actually studied the risky behavior free-roaming cats exhibited in one suburban area of the US and found that 45% of these cats crossed the road.
While many cats cross the road unscathed, others don't. And that's a risk many of us aren't willing to take.
OK, so what are the other reasons we keep our cats inside?
Here are the second most common reasons why we keep our cats inside, regionally:
Europe: protection from people
USA/Canada: protection from wildlife
Australia/NZ: to prevent cats from hunting
All very different reasons, but the same general consensus: "I keep my cats indoors because they could be predators or prey."
But are they actually endangered or endangering other animals or people while outside? We'll get into that more in a bit.
The case for indoor/outdoor cats
Why do some of us allow our cats outside? I bet most cat owners could guess the answer to this one: We believe being outside benefits our cat's mental health.
We see our cat gazing out the window or "chirping" at the wildlife, and we think...wait. They're longing for more enrichment. They're meant to be roaming, wild, and free. You're not alone. 32.9% of cat owners who let their cat outside said it's because their cat indicated they wanted out.
Some also point to data that suggests indoor-only cats tend to be more obese and at higher risk of "feline urological syndrome (FUS)."
But be careful; that doesn't necessarily mean the inverse is true—that outdoor cats are inherently healthier. It just means that indoor cats may be prone to obesity, which can be based on a multitude of factors, including whether or not they sit like lumps all day long in the sun or get exercise.
The concept that cats are "happier" outside hasn't been proven. And sadly, they may encounter more dangers to their health than many owners realize, particularly when they're unsupervised. More on that later.
Which brings us to the most controversial camp of them all: the outdoor-only cats.
The case for outside-only cats
Unfortunately, there isn't a lot of positive data on outside-only house cats. Most data revolves around largely unadoptable wild (feral) cats.
Some are being used to control rat populations in places like Chicago. Other organizations employ trap/neuter/return (TNR) as an alternative to euthanizing feral cats.
Tree House, a well-known organization at the forefront of TNR, also vaccinates the cats they capture with the help of volunteers. In short, it's an alternative to euthanasia and may benefit public health in some regions.
But these are feral studies. What about your non-feral tabby? Unfortunately, the data's pretty grim for outside-only cats. It's generally a more dangerous lifestyle. Cats that live outside may be at increased risk of:
Being hit by a vehicle
Attacks by coyotes, dogs, or even other cats
Exposure to diseases (like the feline leukemia virus)
Poisoning (rodenticides, antifreeze, etc)
Acquiring parasites like fleas and ticks
It's no wonder the lifespan of cats that venture outside (even part-time) tends to be shorter than their indoor friends.
And let's not forget about the flipside. Cats can be predators, too.
Remember, U.S. cat owners are mostly concerned about their cat getting attacked by wildlife—not the opposite. Perhaps many of us even keep the cats because they're great "mousers" or keep gophers at bay.
Or maybe we're not as worried about our cats hunting habits because it's not quite as obvious when our bird population decreases in such a large country compared to smaller impacted islands, where many studies are focused.
Regardless, the data makes it clear: every day spent outside, cats are at an increased risk of becoming predators or prey.
They also get lost. Roughly 52% of the cats in American shelters in 2023 were considered "strays," but they could be someone's pet.
So that makes me curious...
What do cats actually do when they're outside?
I'm going to make the assumption that, like my family, most people with cats that go outside part-time or full-time don't monitor them 24/7.
Starting with cats in the burbs. Here's what those fluffers did:
45% of the cats crossed the road
25% encountered other unfamiliar cats
25% ate or drank "substances" away from home (yikes)
20% explored storm drain systems
20% entered house crawlspaces
Growing up, we lost many outdoor cats to "unknown" causes. Rodenticides, antifreeze, or even a humble citrus fruit could have played a part, but we'll never know.
Now let's look at the predatory side. Cats hunt. Even the well-fed ones.
According to researchers who cross-examined multiple studies, domestic housecats are quite effective hunters, killing 1.3–4 billion birds and 6.3-22.3 billion mammals annually.
Much of the data includes unowned cats, but every cat is born with that hunting instinct. Even the most cuddly, biscuit-making tabbies can be incredible hunters.
So, should I let my cat outside?
We've examined the data. You know your cat. And there's no US law that says you can't let your indoor cat outside (at least for now).
But I think most cat owners can agree that we don't want our cat to meet an untimely or painful end in the great outdoors.
So if you make the decision to allow your cat to be outside for some fresh air and fun, here are some tips to minimize danger.
1. Supervise them the entire time.
While some cats flatten their bodies to the ground in terror when they're outside, others take it as an invitation to roam the neighborhood (particularly if they're former stray cats).
Even putting a tracker on your cat doesn't mean they'll make safe decisions; you'll just know how long they spend at your neighbor's house eating the dog's food.
So how can you ensure your cat's in your sight at all times while outside? Build a giant enclosure! OK, more realistically, consider leash training or build a small catio so they can enjoy some fresh air.
And there's always another option: cat backpacks with proper ventilation. They're also quite entertaining to see in the wild.
2. Make sure they're tagged and microchipped (and belled?)
If your cat does manage to get loose or lost, that tag and microchip will be your best friends. Don't let your furbaby be one of the 52% of stray cats in shelters!
Also, consider adding a bell to your cat's collar. It can help warn birds and other prey in the vicinity if your cat does manage to get out on an impromptu hunting expedition.
3. Keep them up to date on all vaccines and flea and tick medications.
Some outside dangers are big, like cars, and some are teeny but super annoying, like fleas.
A non-insurance wellness plan that can help pay for flea and tick medications is a good thing to consider!
4. Wait until they're at least 6 months old.
This is when they've typically completed their vaccinations, which means an added layer of protection from yuckies. On that note, it's also super important to get your cat spayed or neutered.
Even indoor-only cats can slip outside long enough to contribute to the stray or unwanted litter population.
5. Keep it to daytime-only outings.
Daytime is the winner for safer cat outings. Visibility is better, and you'll have a better chance of finding your cat if they manage to wiggle out of reach.
6. Focus on health, inside and out
While this case is more complex than most give it credit for, I think the data so far suggests cats are safer indoors.
But what if your indoor cat's bored (and getting destructive) or gaining weight sitting inside? Can't you solve that by putting them outside?
OK, here's the thing. Obesity can be dangerous, even life-threatening, for cats. But it's still probably not as dangerous as putting your cat outside full-time. And there's no guarantee your cat wouldn't just sit around outside, like they do on your couch.
Enter: structured, regular playtime. Get your cat engaged, and you'll have fun, too, I promise. Watching a cat leap into the air to catch a play mouse is incredible. Film it in slow motion, and you'll understand how cats can have such a massive impact on bird populations.
The bottom line
Your cat relies on you to make the best decision for their well-being. This is truly your call.
The best thing we can do as cat owners is make informed decisions based on data, research, and our vet's opinion, not just what our neighbors or people on forums say. (Not even what I say!)
The second best thing we can do is consider buying a great cat insurance policy. That way, if an unexpected accident or illness pops up, we're hopefully making care decisions based on our cat's best interests, not agonizing about our bank accounts.