It’s not always obvious if your cat is drinking enough water. Cats don’t usually drink a lot in one go, and how much they need can change depending on what they eat, the weather, and their daily routine.
As a general guide, most cats need about 40–60ml of water per kilogram of body weight each day.
For example:
A 3kg cat needs roughly 120–180ml per day
A 4kg cat needs around 160–240ml per day
A 5kg cat needs about 200–300ml per day
That total includes everything – not just what they drink from their bowl, but also the moisture they get from their food.