How Much Water Should a Cat Drink a Day? Signs of Dehydration + Tips

By the PETME2 Team · Updated October 2026 · General information, not veterinary advice

How much water should a cat drink a day?

As a general guideline, a cat needs about 3.5 to 4.5 oz of water per 5 lb of body weight per day, counting the water in its food.

Cats need water every day to stay healthy. Water helps with digestion, body temperature, and keeping the kidneys and bladder working well.

The most common general guideline is about 3.5 to 4.5 oz (about 100 to 130 ml) of water per 5 lb of body weight per day. This is the total from all sources: the water bowl, the fountain, and the moisture in food.

Here is what that looks like by weight:

General guideline for healthy adult cats. Hot weather, activity, illness, and diet can all change how much water your cat needs. Your vet can tell you what is right for your cat.

Wet food vs dry food: why it matters

Wet (canned) food is mostly water, often around 75% to 80%. Dry food (kibble) is usually only around 10% water. This makes a big difference:

• A cat on wet food gets a lot of its water from meals. It may drink very little from the bowl, and that can be normal.
• A cat on dry food gets almost no water from meals, so it needs to drink most of its water from the bowl or fountain.
• A cat on both is somewhere in the middle.

So if your cat eats mostly wet food and you rarely see it drink, that alone is not always a worry. But if your cat eats dry food and hardly drinks, it is worth paying closer attention.

How to tell how much your cat drinks

It is hard to see, because cats take small sips throughout the day. A simple way to check:

1. Measure the water you put in the bowl in the morning with a measuring cup.
2. Measure what is left 24 hours later.
3. The difference is roughly how much your cat drank (a little is lost to evaporation, and other pets will change the number).

Do this for a few days to learn your cat's normal. Then you will notice if it changes.

Why is my cat not drinking water?

Usually it is something simple, like stale water, a dirty bowl, a poor spot, or a wet food diet. A sudden drop in drinking should be checked by your vet.

Cats come from desert ancestors and often have a low thirst drive. Many simply do not drink much. But there are common, fixable reasons a cat may avoid its water:

• The water is not fresh. Water that sits all day can collect dust, hair, and food bits. Many cats skip it.
• The bowl is dirty. A slimy film (biofilm) builds up on bowls and fountains. Wash them often.
• The bowl is the wrong shape. Some cats do not like their whiskers touching the sides of a narrow, deep bowl. A wide, shallow dish may help.
• The water is next to the food or litter box. Many cats seem to prefer water a few feet away from food and far from the litter box.
• They prefer moving water. Some cats would rather drink from the faucet. Read why cats like running water.
• Stress or change. A move, a new pet, or a loud spot near the bowl can put a cat off drinking.
• They eat lots of wet food. As above, they may just need less from the bowl.

If your cat suddenly drinks much less than usual, stops eating, or seems unwell, do not wait. Call your vet. And if your cat suddenly drinks much more than usual, that is also worth a vet visit, because increased thirst can be a sign of some health problems.

What are the signs of dehydration in cats?

Common signs include low energy, dry or sticky gums, sunken eyes, skin that is slow to fall back when gently lifted, and less urine than usual.

Dehydration means your cat's body has lost more water than it has taken in. Some cat dehydration signs you can check at home:

• Low energy or hiding more than usual.
• Dry or sticky gums. Healthy gums are usually moist and slippery.
• Sunken or dull-looking eyes.
• Skin tenting: gently lift the skin between the shoulder blades and let go. In a well-hydrated cat it falls back quickly. If it stays up or falls back slowly, your cat may be dehydrated. (This test is less reliable in older or very thin cats.)
• Less urine in the litter box, or smaller clumps than normal.
• Not eating, vomiting, or diarrhea, which can cause and worsen dehydration.
• Constipation or hard, dry stool.

When to call the vet: dehydration can become serious quickly in cats. If you see these signs, especially with vomiting, diarrhea, not eating, or weakness, contact your veterinarian right away. Do not try to force water into your cat's mouth.

How can you get your cat to drink more water?

Offer fresh water daily, keep bowls clean, place water away from food and the litter box, add some wet food, and try moving water if your cat likes it.

1. Give fresh water every day. Empty, rinse, and refill bowls at least once a day.
2. Keep bowls and fountains clean. Wash bowls often and clean fountains on a regular schedule. See how often to clean a cat water fountain.
3. Add more water spots. Put water in a few quiet places around the home, especially in multi-cat homes.
4. Move water away from food. A few feet apart is enough for many cats.
5. Try a wide, shallow bowl made of stainless steel, ceramic, or glass.
6. Add wet food to your cat's diet, if your vet agrees. It is an easy way to add water.
7. Try a water fountain. Many cats seem to like moving water, and a filter helps keep it cleaner.

Can a water fountain help a cat drink more?

A fountain keeps water moving and runs it through a filter. Many owners say their cats drink more often from a fountain than from a still bowl, though every cat is different. A fountain also holds more water, so the supply does not run out during the day.

A fountain only helps if it stays clean. Wash it and change the filter on schedule. Our filter guide explains how.

All PETME2 fountains come apart for cleaning, use quiet pumps, and have filters:

• 3.2L Stainless Steel Fountain: large capacity in stainless steel. See stainless steel vs plastic vs ceramic.
• 2.2L Transparent Fountain: clear tank, so you can see the water level at a glance.
• 2L Quiet Fountain: simple and quiet, with a low-water light.
• 2.2L Fountain with Stainless Steel Tray: a stainless steel drinking tray that is easy to wipe clean.

Browse them all in the water fountain collection.

Does food affect how much water a cat drinks?

Yes. Wet food is mostly water, so cats on wet food drink less from the bowl, while cats on dry food need to drink more.

Drinking is tied to eating. Cats often drink around mealtimes, so steady meal times can mean steadier drinking too. If you feed dry food, keep a fountain or bowl close to the feeding area (but not right next to the food). To find the right food amount for your cat, see how much should a cat eat.

Frequently asked questions

How much water should a 10 lb cat drink?

As a general guideline, a 10 lb cat needs about 7 to 9 oz of water a day in total, or roughly one cup. That includes water from food, so a cat on wet food may drink much less from the bowl. Ask your vet what is normal for your cat.

Is it normal for a cat not to drink water?

Cats on mostly wet food may drink very little, and that can be normal. But a cat on dry food that rarely drinks, or any cat that suddenly drinks much less, should be checked by a vet.

Why isn't my cat drinking water?

Common reasons include stale water, a dirty bowl, water placed next to food or the litter box, or a bowl your cat dislikes. Cats on wet food also drink less, because their food is mostly water. If your cat suddenly drinks much less than usual or seems unwell, call your vet.

How long can a cat go without water?

Not long. Cats can become dehydrated within a day or so, and faster in heat or if they are sick. If your cat has not had water, is not eating, or seems weak, call your vet right away.

Why is my cat drinking so much water?

Hot weather, more play, or a switch to dry food can increase thirst. But a big, lasting increase in drinking can be a sign of health problems, so it is worth talking to your vet.

How can I tell if my cat is dehydrated?

Look for low energy, dry or sticky gums, sunken eyes, skin that is slow to fall back when gently lifted, and less urine in the litter box. If you see these signs, contact your vet.

How do I get my cat to drink more water?

Give fresh water every day in a clean, wide bowl, and place it away from the food bowl and litter box. Offer more than one water spot, add some wet food if your vet agrees, and try a fountain if your cat likes moving water.

How can I measure how much water my cat drinks?

Fill the bowl or fountain with a measured amount using a measuring cup, then measure what is left 24 hours later. Set out a second container in the same room that your cat cannot reach to estimate evaporation. Remember that wet food adds water too.

Does wet food count as water for cats?

Yes. Wet food is mostly water, so it adds a lot to your cat's daily intake. Dry food adds very little, so cats on dry food need to drink more.

Do cats drink more from a fountain?

Many owners say their cats drink more often from a fountain, but not every cat does. What matters most is clean, fresh water. A fountain with a filter, cleaned on schedule, is one easy way to offer that.

Why does my cat cough after drinking water?

An occasional cough or gag can happen if a cat drinks fast and a little water goes down the wrong way. Coughing that happens often, or comes with breathing changes, low energy or other signs, should be checked by your vet.

Why does my cat scratch the floor before drinking water?

No one knows for certain. Common ideas include instinct, leaving scent from glands in the paws, or simple habit. It is usually harmless, but a non-slip mat under the bowl can protect your floor.

Should I put ice cubes in my cat's water?

Some cats enjoy cool water, especially in summer, and a few ice cubes are fine for most cats. If your cat avoids it, keep the water at room temperature.

This article is general information, not veterinary advice. If your pet seems unwell, talk to your veterinarian.