Why Do Cats Lick Windows?

It’s the start of a brand new day and you pull open the blinds to let the sunshine in when you notice your little cat jump on the window sill.

You think to yourself, “Oh, my little feline friend is going to see what’s going on in the neighborhood or maybe check out some birds. “

Instead, your cat vigorously licks the windows and ignores any and all outside activity! If this sounds like your morning, you’re not alone!

But why do cats lick windows? The most likely reason is that cats like to lick the moisture off the windows. In the wild, standing water could be dangerous so cats instinctively seek out fresh, moving water and the moisture on windows is a perfect source. In other cases, cats might just be bored or enjoy the texture on their tongue. 

While finding a unique water source is the most likely reason, it’s certainly not the only one! So let’s look at all the possible reasons why our feline friends might lick windows and whether or not we should be worried about their weird behavior.

Reason 1: Your Cat Likes Unique Sources of Moving Water

As temperatures outside your home drop, the warm air inside comes in contact with the cool glass and leaves moisture on the window. This process is called condensation and the result is small droplets of water on your window. If your home is particularly humid you can expect more water to form but regardless of the amount of moisture, cats will be happy to track it down and lick it up!

But why would our cats want to drink window water instead of the fresh water in their bowl?

It has everything to do with our cat’s wild instincts that warn them about the dangers of standing water. Standing water is more likely to contain parasites and pathogens that could harm our cats- at least in the wild. While that’s no longer a real danger for an indoor-only feline the instinct remains and cats are naturally drawn to moving water sources.

Even though the water on our windows isn’t running in the same way as a freshwater stream, it’s still a great source of fresh and clearly not stagnant water. It’s sort of like the indoor cat equivalent of licking the morning dew off the grass.

But even if cats have other sources of running water available to them (I use this Catit water fountain on Amazon to give my cat the running water “experience”) cats will often still pursue other sources of water. Studies from the folks at Royal Canin support this idea that cats like variety in their water sources concluding that “cats apparently like to use different drinking options, and should therefore be offered several possibilities.” The study also found that “cats seem to prefer their water to be provided in a small bowl located away for their food bowl” so the location of your cat’s water bowl could also be a factor that motivates your cat to lick windows.

Finally, licking the window can give your cat a chance to enjoy water with a different flavor. While the taste of window water might not sound appealing to you, it certainly provides some variety that our cat might enjoy.

Reason 2: Your Cat Enjoys The Texture and Temperature

What if there’s very little or even no water on the window?

In those cases, cats may just enjoy the texture and temperature of the window on their tongues. I know, it seems a little weird but the glass on a window offers a unique texture that could feel interesting on a cat’s tongue. Additionally, windows are often cooler and some cats might enjoy this too.

In most cases, cats probably started licking windows to collect some of the moisture but may have found that they enjoyed the feel of licking windows even when there isn’t any more water! The same thing seems to happen to cats that pick up the habit of licking shower curtains.

Reason 3: Your Cat Likes The Attention

While licking windows may have started as a novel way to get some freshwater, your cat may have enjoyed the attention they got from you when they licked the window. While this doesn’t explain why cats will start a silly behavior I think it can explain why many cats continue them.

Chances are that when you see your cat lick a window you don’t just move on with your day- instead, you take a few moments to watch your feline friend and probably talk to them or at least laugh a little. Your cat will quickly learn that licking windows not only provides an interesting water source but also gets some extra attention from their favorite human!

Reason 4: Your Cat Is Bored and Curious

Cats don’t honestly need much of a reason to do silly things and licking a window could just be the latest feline experiment by your cat. Many cats just seem to lick everything they can find and for some cats, this even includes licking people so it’s not a stretch to imagine that these licky cats would be willing to give the window a try!

What may have started as a whim could then be encouraged by any of the other reasons on this list. For example, cats may have decided to give the window a lick for fun and they enjoyed the attention you gave them for being silly along with a little bit of water. All of these reasons can work together to create a committed window licker!

Plastic Windows Change Everything!

Most windows are made from glass but it’s not uncommon to find plastic windows, too. While cats will lick plastic windows for all of the same reasons above, there may be a few additional motivations as well.

Some plastic, like the kind found in plastic bags, can contain beef tallow which will encourage some cats to lick while others will just happily sit on the bag and enjoy the essence of beef tallow around them. While plastic bags may seem pretty different from plastic windows, in many cases both would be treated with the same tallow-based lubricant. While our human senses have no chances of picking this up, it’s easy work for our cat’s super-powerful sense of smell.

Other plastics, like those found in shower curtains, may contain corn starch which some cats may enjoy. While it could seem like a stretch that our carnivorous cats would enjoy corn starch when you consider the corn-based ingredients of popular budget cat foods like Meow Mix it starts to seem pretty reasonable!

Finally, some plastics may mimic pheromones that our cats find interesting. This could be a big factor in explaining why some cats love lick blinds and while cats will react differently to these pheromone smells and licking is a common response across multiple types of plastics.

Should You Worry About Your Cat Licking Windows?

While it can be a little weird, licking windows typically isn’t a problem for cats. However, if you’re using a particularly toxic cleaner or your window is very cold then you may need to worry.

Let’s take a closer look.

Window Cleaning Products and Cats

Having your windows licked by your cat isn’t likely to make them look amazing so you might find yourself cleaning them a bit more as your cat picks up this habit.

But should you be worried about your cat ingesting window cleaners?

According to Pet Poison Helpline, most general purpose cleaners (like Windex and 409) are mostly safe and the risk should be low unless your cat is licking these cleaners directly off the window. But in most cases, you’re spraying the window and wiping it down which will remove most of it from the window. It’s still a good idea to avoid these cleaners if your cat is licking windows or make sure they don’t have direct access immediately after you’ve cleaned them.

If you’re using vinegar and water, which is a popular eco-friendly alternative, the risk will depend on how you dilute the vinegar. According to the ASPCA, undiluted vinegar can cause irritation, diarrhea, and vomiting in cats. However, you wouldn’t actually clean with undiluted vinegar and most people suggest a much safer 1 part vinegar to 10 parts water for window cleaning.

If you’re on the other end of the spectrum and you’re using a more powerful cleaner, like bleach, then the risk is a lot greater though I wouldn’t expect anyone is using these types of products on their windows.

While the risk may be low, pay attention to your cat’s window licking habit and make sure they aren’t licking the windows too soon after you clean them. You should also consider cleaning your window with plain water if your cat just loves licking the window.

Stuck Tongues and Frozen Windows

Okay, the risk of this is pretty low but it’s something to consider if you’re living in a very cold environment where the surface of the window could be freezing. When a wet tongue touches a freezing surface, the salvia on the tongue becomes frozen to that surface. We’ve all heard the stories of tongues getting stuck to flag poles…and it’s true! This can absolutely happen!

But can it happen to our cats?

It’s possible- but unlikely. The surface of the window would need to be below freezing. It’s also more likely to happen on metal as opposed to glass. While almost all windows include some metal, it’s usually not in the same spots that cats lick. Even though windows can get very cold, it’s also unlikely that they’ll reach the below-freezing temperatures required for this to happen.

Still, if your cat loves licking windows and you live in a northern region, this may be something to consider.

How Can I Stop My Cat From Licking Windows?

It’s rarely easy to get a cat to simply stop a behavior; instead, it’s much easier to think in terms of redirecting the behavior. In other words, we want to find out why our cat is engaging in the behavior, find a way to replace it and discourage the undesirable behavior.

For example, cats that jump on counters may be acting out on the feline instinct to find heights. Rather than try to punish them for pursuing their instincts, we can provide a cat tree that’s taller than the kitchen counter so they have a more appropriate place to get the perfect vantage spot. Additionally, we can find a way to discourage cats from jumping on the counter and make the area less appealing so they’re even more likely to use the cat tree.

The same is true for a window licking habit although it can be a bit more difficult to pin down what’s motivating our cats. As we’ve already discussed, the most likely reason that cats are interested in licking the windows is a novel source of water. If you’re currently only offering your cat one traditional standing water bowl this even more likely as we know that cats like moving water from various sources. Considering adding a water fountain bowl to your home (I recommend the Catit bowl on Amazon) or simply add more bowls to your house in different locations. Ideally, place a water bowl near the main window that’s being licked so your cat can still associate that area with water.

Finally, you’ll want to reduce access to the windows to try and break the habit. You can do this by closing the blinds, adding a barrier to the window sill, or limiting your cat’s access to the room where they lick windows the most. The idea here isn’t to do this permanently but just until the habit is redirected to more appropriate areas.

If you think your cat is motivated by some of the other reasons on this list, then things can be a bit more complicated. Still, it’s likely that water motivated your cat at some point so adding additional water locations is a good start.

Closing Thoughts

We can add licking windows to the long list of weird things that our cats do. While it could seem like a completely impractical and silly behavior, if cats are licking windows for water then it’s actually a relatively practical behavior since finding moving freshwater would have helped our cat’s ancient ancestors survive.

While there are other reasons for licking windows, it’s a safe bet that the behavior usually started by tasting a little window water. But from there, the behavior could have changed into a variety of motivations.

Besides having dirtier windows, it’s usually not a problem to have our cats lick windows as long as they’re not being directly exposed to any window cleaner!

What do you think? Which reason most likely explains why your cat licks windows?