How Much Water Does a Cat Need as an Adult?

Brown and white cat sipping water from cat bowl

To maintain good health, cats require new drinking water every day. For the kidneys to effectively remove toxins from the blood, water is crucial. Dehydration in cats, whether brought on by disease or a lack of fluids, is serious and, if left untreated, can be fatal.

Cats with acute or chronic renal insufficiency may need additional fluids either intravenously or subcutaneously. The latter therapy is quite simple to learn and practice, and is frequently done at home. The majority of cats show noticeable improvement following these treatments.

Excessive Water Intake

A cat who drinks a lot of water may have or diabetes. Even though cats may naturally drink more when it's hot outside, it's crucial to understand how much water a cat typically consumes. An emergency veterinarian visit is necessary if they start drinking big amounts of water all of a sudden and exhibit other signs.

Water Needs Depends on Diet

About 67 percent of the tissues in a cat's body are made of water. By coincidence, that is roughly the amount of water in the food they hunt and consume in the wild. When compared to canned cat food, which has at least a 75 percent moisture content and is a rich source of hydration, dry cat food only contains 6 to 10 percent water. A cat eating just dry food would thus need more extra drinking water than a cat eating only raw or canned food. A cat eating both canned and dry food will also require extra water to stay hydrated.

According to a calculation developed by Dr. Jennifer Coates and published in a article, a 10-pound adult cat eating dry food daily needs around a cup of water. A third of a cup of water per day is required by the same cat on a canned diet.


  • Keep fresh, clean water available at all times for all cats, regardless of diet, preferably with an .
  • Watch for signs of dehydration. A good test is to pull up the loose skin at the nape of the neck. If it springs right back, the cat is sufficiently hydrated. If it is slow to recede, suspect dehydration. Try adding water to your cat's canned food or adding an ice cube or two to their drinking water to make it more interesting. If the neck skin does not appreciably recede, and the cat shows any other sign of sickness, call your veterinarian immediately.
  • Know your cat's drinking habits. If they suddenly go "off water" or start drinking excessive amounts regularly, call your veterinarian.


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