How Much Water Should a Cat Drink a Day?
A healthy cat's daily water need is usually given by body weight, and two veterinary sources we checked land in the same place. Food counts too: VCA notes that cats who eat canned food don't have to drink as much water, because the food supplies some of it.
Below: the numbers, how food changes them, the simplest signs of dehydration, ways to encourage drinking, and when a change in drinking means a call to the vet.
Key takeaways
- About 4 ounces of water per 5 pounds of body weight a day, according to VCA, or 40 to 60 ml per kg, according to the Ontario Veterinary College.
- Water from food counts, per VCA. Wet food is typically more than 65 percent moisture and dry food less than 20 percent, per the OVC team.
- Dark yellow urine can be a sign of dehydration.
- A sudden increase in drinking is a reason to call your vet.
The numbers
VCA Animal Hospitals gives a rule of thumb of four ounces of water for every five pounds of body weight, so a 10-pound cat needs about 8 ounces a day. The Ontario Veterinary College pet nutrition team gives 40 to 60 ml per kg of body weight: roughly 160 to 240 ml a day for a 4 kg cat.
Those two figures agree. Four ounces per five pounds works out to about 52 ml per kg, inside the OVC range. VCA adds that the real need shifts with temperature, weight, diet, health and activity, so treat these as guidelines, not targets.
Food counts as water
According to the OVC team, wet food typically contains more than 65 percent moisture and dry food less than 20 percent. VCA puts it simply: cats who eat canned food do not have to drink as much water.
In other words, a cat on dry food gets less of its water from its food than a cat on wet food does.
Signs your cat may not be drinking enough
The OVC team says dark yellow urine may indicate dehydration, while clear urine suggests a well-hydrated pet, and that a dehydrated animal produces less urine. A clean litter box makes changes easier to spot; see our guide on how often to change cat litter.
Ways to encourage drinking
VCA suggests placing bowls near where your cat sleeps or rests and away from the litter box. It notes that some cats dislike their whiskers touching the sides of a bowl and that cats tend to prefer glass, metal or ceramic bowls over plastic. Wash and rinse bowls daily and change the water often.
Some cats enjoy drinking from running water, VCA says; if you use a fountain, clean the filter weekly or as the maker directs. The OVC team notes that app-connected fountains can track intake but are not essential. Neither source says a fountain makes a cat drink more.
VCA also suggests adding about a teaspoon of low-sodium chicken broth with no added spices to water, changed daily. For more on indoor enrichment, see our picks for interactive cat toys.
When drinking more is a warning sign
The Cornell Feline Health Center lists excessive thirst and urination among the signs of diabetes in cats, and says that the most common signs of hyperthyroidism include increased thirst and urination, alongside weight loss and increased appetite. We cannot tell you what a change means for your cat; a sudden increase in drinking is a reason to call your veterinarian.
FAQ
How much water should a 10-pound cat drink a day?
About 8 ounces, using VCA's rule of four ounces per five pounds of body weight. Water from wet food counts toward that.
Does wet food count as water intake?
Yes. Wet food is typically more than 65 percent moisture, according to the Ontario Veterinary College team, and VCA says cats on canned food do not need to drink as much.
How can I tell if my cat is dehydrated?
Dark yellow urine and less urine than usual can be signs, according to the OVC team. If you are worried, call your vet.
Do cats need a water fountain?
They are not essential, according to the OVC team. VCA says some cats enjoy running water, but neither source says a fountain increases how much a cat drinks.
Why is my cat suddenly drinking a lot?
Increased thirst can be a sign of conditions including diabetes and hyperthyroidism, according to the Cornell Feline Health Center. Only a vet can tell you why.
Editor's note: Sources were read on September 24, 2026. This guide is general information, not veterinary advice.
