A cat can drink distilled water without being harmed by a bowl of it, but making it the permanent supply is solving the wrong problem. Distillation strips everything, minerals included, and cats get most of their water intake alongside food anyway. If you are reaching for jugs because the tap tastes or smells wrong, the tap is the thing to fix.
Why people ask this in the first place
Almost nobody buys distilled water for a cat out of nowhere. The trigger is usually a fountain furring up with white crust, a bowl that grows a film, a vet mentioning urinary crystals, or a household that already distrusts its own tap. Each of those has a different fix, and only one of them is about the water being too mineralized. Working out which trigger applies to you decides whether any purchase is needed at all.
What distilled water changes and what it does not
Distillation boils water and condenses the vapor, leaving dissolved minerals and most contaminants behind in the boiler. The result is flat tasting and carries no calcium or magnesium, which is why it stops the white crust in a fountain. It does not make a bowl self cleaning: the slime that forms in a pet bowl is biofilm from saliva and food, and it will grow in distilled water just as happily. Wash the bowl daily either way.
Diet questions belong to a vet, not a filter seller
Whether a cat with a diagnosed urinary or kidney condition should get low mineral water is a clinical judgment, and any treatment company that tells you otherwise is selling past its competence. What we can say plainly is that no water treatment device is a medical device, and a change of drinking water is not a treatment plan. Ask the veterinarian who made the diagnosis, and take the answer from them.
The household fix that actually helps
If the concern is what is in the water, test it rather than substitute it. Households on a private well are responsible for their own testing, and a bad result is invisible in a bowl. Our well water testing guide sets out the sequence. Once you know the result, a carbon filter for taste and chlorine, or a softener for scale in the fountain, treats every tap in the house including the one you fill the bowl from.
Questions people ask about can cats drink distilled water
Will distilled water hurt a cat?
A bowl of it is not harmful. The concern with a permanent distilled supply is that it supplies no minerals at all, which is a question for your veterinarian.
Does distilled water stop the white crust in a pet fountain?
Yes, because the crust is dissolved hardness minerals left behind as water evaporates, and distillation removes them before they reach the bowl.
Is filtered tap water good enough for a cat?
For most households yes. A carbon filtered tap removes the chlorine smell that puts some cats off drinking, at a fraction of the effort of buying jugs.
Should well owners give pets bottled water?
Not automatically. Test the well first: the EPA notes private wells are not federally regulated, so nobody else is checking that supply for you.