How Much Water Should a Cat Drink?

Why cats drink so little

Cats are thought to have descended from desert-dwelling ancestors that got most of their moisture from prey. Whatever the history, many pet cats today show a weak urge to drink and will tolerate mild under-hydration without seeming bothered.

This is why it is common to see a healthy cat that rarely visits the water bowl. It also means that when a cat does start drinking a lot, it is more noticeable and more meaningful than it might be in a dog.

As a loose guide, total daily water needs for a cat are often put in a similar per-kilogram range to dogs, and the Petopedia calculators can give you a ballpark figure for your cat's weight. The key word is total: that figure includes water from food, not just from the bowl.

How much comes from food

Diet makes the biggest difference to how much your cat drinks.

Diet	What to expect at the bowl
Mostly wet food	Very little drinking; much of the daily water comes from the food
Mixed wet and dry	Moderate drinking
Mostly dry food	Noticeably more drinking, as kibble contains little moisture

Wet food is mostly water, so a cat eating it may get most of what they need from meals alone. Some vets suggest including at least some wet food for cats that drink very little, particularly those with a history of urinary problems. Guidance varies from cat to cat, so it is worth discussing with your vet rather than changing diet abruptly.

If you do change your cat's food, do it gradually over a week or so, and expect their drinking to shift.

Making water more appealing

Many cats are particular about where and how they drink. Small changes can encourage more regular drinking.

Bowl choice

• Use a wide, shallow bowl. Some cats dislike their whiskers touching the sides.
• Ceramic, glass or stainless steel are easy to keep clean. Some cats seem to dislike plastic, possibly because of smell.
• Fill it to the brim so your cat doesn't have to put their face deep inside.

Placement

• Keep water away from the food bowl. Many cats prefer to drink in a separate spot.
• Keep it well away from the litter tray.
• Choose quiet places away from busy walkways, noisy appliances and other pets that might guard the area.
• Offer several bowls around the home, including on different floors. This matters more in multi-cat households.

Freshness

• Change the water at least once a day and wash the bowl regularly.
• Some cats prefer water that is slightly cool.

Fountains Many cats are drawn to moving water, and a pet water fountain can encourage some to drink more. Not every cat takes to one, and some are wary of the noise at first. If you try one, keep a still bowl available too, and clean the fountain and replace any filter as the manufacturer advises. A dirty fountain can put a cat off entirely.

A few cats like to drink from a dripping tap or a glass on the table. If it is safe, there is no harm in indulging the habit, but don't rely on it as their main source.

Signs of dehydration

Dehydration can develop when a cat is unwell, off their food, vomiting, has diarrhoea or is in a hot environment. Signs include:

• Dry or tacky gums
• Lethargy, hiding more than usual or seeming flat
• Reduced appetite
• Sunken-looking eyes
• Skin at the scruff that is slow to return when gently lifted
• Less urine in the litter tray, or small, hard clumps

The skin test is only a rough guide, especially in older or thin cats. Cats also hide illness well, so a quiet change in behaviour is worth taking seriously.

A cat that has stopped eating is a particular concern. Cats can become seriously unwell if they go without food for even a short time, and they often stop drinking too. If your cat hasn't eaten for a day or more, contact your vet.

When increased thirst matters

Drinking clearly more than usual, for more than a few days, is one of the more useful early warning signs in cats. It is linked with a range of medical conditions that become more common as cats age, and many are easier to manage when found early.

Things you might notice:

• Visiting the water bowl far more often
• Emptying bowls that used to last all day
• Drinking from unusual places, such as taps, sinks, plant pots or the shower
• Bigger or more frequent clumps in the litter tray
• Urinating outside the tray

It isn't possible to tell the cause at home, so the sensible step is a vet appointment. Your vet may suggest blood and urine tests to look for the reason.

Keeping track at home

Measuring a cat's water intake is harder than a dog's, because they drink small amounts and some water evaporates. Still, a rough measure is useful.

1. Fill the bowl with a measured amount from a jug.
2. Measure what is left after 24 hours.
3. If you want to account for evaporation, leave an identical bowl of water somewhere your cat can't reach and subtract what that loses.
4. Repeat for a few days to get a typical figure.

Litter-tray changes are often just as telling. A tray that suddenly needs much more frequent clumping is worth noting.

Logging water and litter observations in Petopedia builds a picture of your cat's usual pattern, so a gradual rise is easier to see. Our guide to knowing your pet's normal explains how to build that baseline, and indoor cat enrichment has ideas for setting up a home that suits your cat.

When to talk to your vet

Contact your vet if your cat:

• Is drinking noticeably more than usual for more than a few days
• Is producing more urine, or urinating outside the litter tray
• Has stopped eating, or is eating much less, for a day or more
• Shows signs of dehydration, especially with vomiting or diarrhoea
• Is straining in the litter tray or producing little or no urine — this can be an emergency, particularly in male cats, so call your vet straight away
• Is losing weight, hiding or behaving differently

Bring any notes you have about drinking and litter habits. Petopedia helps you notice changes, but it doesn't replace a vet's examination. See signs your pet needs a vet for more.