How much water should a cat drink?
Drinking noticeably more is one of the earliest signs of serious illness — and one of the easiest to miss.
The rough figure
Around 50ml per kilogram of bodyweight per day from all sources — so about 200–250ml for a typical 4–5kg cat. A cat on wet food gets most of that from the food itself and may barely touch the bowl. A cat on dry food must drink nearly all of it.
Why cats drink so little
Domestic cats descend from desert-dwelling ancestors and evolved to extract most of their water from prey, which is roughly 70% water. Their thirst drive is correspondingly weak, and it does not fully compensate when they eat dry food. Mild chronic dehydration is common and contributes to urinary problems.
Increasing intake
- Add wet food. The single most effective change, even partially.
- Move the bowl away from food. Cats instinctively avoid drinking near where they eat.
- Use wide, shallow bowls. Narrow bowls press on whiskers, which many cats dislike.
- Try a fountain. Moving water is more attractive to many cats than still water.
- Multiple stations around the house, including upstairs.
- Ceramic or glass rather than plastic, which can taint the taste.
Drinking more is a red flag
A cat that starts emptying the bowl, drinking from taps, or producing noticeably heavier litter clumps needs a vet appointment. Increased thirst is a classic early sign of chronic kidney disease, hyperthyroidism and diabetes — all common in older cats and all far more manageable when caught early.
How to measure it
Fill the bowl with a measured amount, cover other water sources for a day, and measure what is left. Do it over two or three days for an average. Bring the figure to your vet — it is far more useful than "seems to be drinking more".
Signs of dehydration
Lift the skin between the shoulder blades: it should spring straight back. Sunken eyes, tacky gums and lethargy all suggest dehydration, which in a cat that has stopped eating is a same-day veterinary matter.
Convert your pet's age
Human-year equivalent, life stage, and when senior care should begin.
Open the age calculator →Cats hide illness well, so a change in drinking is often the first visible sign. Know the other early signals before you decide it is nothing. Signs a cat is in pain →
Common questions
How much water should a cat drink daily?
Roughly 50ml per kilogram of bodyweight from all sources, so about 200–250ml for a 4–5kg cat. Cats fed wet food get most of this from their food and may drink very little.
Why is my cat suddenly drinking a lot?
Increased thirst is a classic early sign of chronic kidney disease, hyperthyroidism or diabetes, all common in older cats. It warrants a vet appointment rather than watching and waiting.
Do cats need a water fountain?
Not necessarily, but many cats drink more from moving water. Other simple changes help too: wide shallow bowls, several stations, and keeping water away from the food bowl.