Hepper is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

How Often to Change Cat Water? Vet-Approved Care Facts

Grant Piper

By Grant Piper

hand pouring pure water from a glass into a bowl for a domestic cat

Vet approved

Dr. Lauren Demos  Photo

Reviewed & Fact-Checked By

Dr. Lauren Demos

DVM (Veterinarian)

The information is current and up-to-date in accordance with the latest veterinarian research.

Learn more »

Cats need a steady diet of food and water to survive. Most people are good about leaving water out for their cats, but are you changing out the water enough? Many people simply refill the bowl when it runs low, but that is often not good enough. Cats can be picky about water and ensuring that the water is fresh and clean at all times is imperative for your cat’s health. You should change your cat’s water daily if possible. You should also ensure that the bowl is clean. What if you use a water fountain or gravity feeder? How long can you leave your cat’s water? This guide will answer those questions and more in a bid to ensure that your cat gets the best and freshest water possible for their health.


How Often Should You Change a Cat’s Water Bowl?

If you give your cat water from an open bowl, you should change their water daily. Even if it does not look like your cat has drunk very much from the day before, you should still change out the water every single day. If you cannot change the water daily, you should absolutely change the water every other day. You should never let your cat go more than 2 days without changing the water out. As we will explore later in this article, doing so minimizes the amount of time for bacteria to grow and contaminate the water. It also gives you an idea of how much water your cat is drinking daily, which can indicate changes in their health.

pouring water at cat or dog feeder
Image Credit: Nina Lishchuk, Shutterstock

How to Change Your Cat’s Water

Some people simply refill their cat’s bowl when it is empty, but that is not the best way to change your cat’s water.

You should change your cat’s water by following these steps for safety and cleanliness:
  • Dump out your cat’s old water.
  • Rinse the water bowl out.
  • Clean the water bowl with soap and rinse again.
  • Refill the water bowl with fresh water.
  • Repeat daily (either in the morning or in the evening).

How Often Should You Change a Cat’s Water Fountain?

Some owners use a water fountain instead of a bowl. Water fountains circulate the water and often include a filtration system. Water fountains each have their own recommended settings and cleaning schedules. You should consult your water fountain’s individual user manual for specific advice about how to care for your machine and your water.

However, the recommendation is to change the water in your cat’s fountain every 3 to 5 days. Some fountains can be changed once a week, but it depends on what kind of filters your system has. You also want to ensure that you are changing out the water filter at the appropriate interval in addition to changing out the water in the fountain.

If you want to encourage your cat to drink more water, a great cat water fountain can be just the thing.

Hepper Stainless Steel Cat Water Fountain
  • Premium 304-Grade Stainless Steel - This metal cat water fountain is hygienic, with superior...
  • Serene & Healthy Cat Drinking Fountain Experience - With whisper-quiet pumping & an advanced...

Our Hepper Stainless Steel Cat Water Fountain has a minimalist, modern design, advanced triple filtration, and adjustable water flow. This fountain is quiet, sturdy, and easy to clean, making it a low-fuss addition to your home. 

Cat Water Changing Schedule

Type of Waterer Change Interval
Water Bowl Daily
Gravity Waterer (Jug) 1–3 days
Short Fountain* 1–3 days
Average Fountain* 3–5 days
Long Fountain* Weekly

*Consult your fountain’s user manual for detailed instructions about replacing and changing water.

Cat drinking fountain in the shape of a flower with water
Image Credit: Pavel105, Shutterstock

hepper single cat paw divider

Why You Need to Change Your Cat’s Water

Changing your cat’s water is extremely important for a number of reasons. First, changing the water prevents it from growing harmful bacteria. Old water, especially water that gets food particles or debris in it, can grow bacteria, which can make the water taste bad or even cause your cat to get sick. Changing the water also helps keep it fresh. Other things can fall into the water, such as dust or dirt. Standing water can also grow algae or accumulate a film on the surface. Some cats will refuse to drink standing or stagnant water that they feel is soiled. Keeping the water fresh will help ensure that your cat will continue to drink and stay hydrated.

Should You Wash Your Cat’s Water Bowl?

Yes. In addition to dumping and replacing your cat’s water, you should also clean the bowl. Cleaning the bowl prevents any bacteria from stubbornly building up. It can also remove grime, film, and dirt that can get stuck to the bottom of the bowl. The sides of the bowl can also get things stuck on them from your cat’s tongue while they are drinking, including dead skin, saliva, fur, or food. Rinsing out the bowl is often not enough to break up these deposits, especially if you go for longer periods without washing the bowl.

For the best results and the safest results, you should wash your cat’s bowl every day while you are refilling it. Just use some simple dish soap and scrub out the bowl. It only takes a few seconds, and it will leave your cat’s bowl clean and fresh. Adding fresh water to a dirty bowl can remove the benefits of putting in fresh water in the first place. Get in the habit of cleaning your cat’s bowl while you are replacing the water for maximum benefit.

You can also run your water bowl through the dishwasher if it is dishwasher safe. If you set the dishwasher to run with hot water and steam dry, it will kill most microbes hiding in the bowl. Most water bowls are dishwasher safe, but you should double check just to be safe.

man holding cat bowl
Image Credit: Jaromir Chalabala, Shutterstock



Most people provide water for their feline friends using a simple open water bowl. If you use a water bowl, you should change the water daily and clean the bowl out when you change the water. This will ensure that your cat’s water is always clean and fresh. You should never leave your cat’s water for more than 2 days without being changed. Leaving water out for too long can breed bacteria and create a grimy, unappetizing water source that will prevent your cat from drinking as much as they need.


Featured Image Credit: goodbuka, Shutterstock

Related Articles

Further Reading

Vet Articles

Latest Vet Answers

The latest veterinarians' answers to questions from our database