Why Your Cat Keeps Using the Bath as a Toilet

If you are lucky enough to share your home with a cat you will know they are creatures of habit, and quirky ones at that. When it comes to bathroom habits it can be particularly baffling to wake up, wander into the bathroom, and discover your cat has used the bathtub as a toilet... again.

If you’ve found yourself staring at the tub wondering why on earth they’d choose that spot, you’re not alone. It’s a surprisingly common feline behaviour that leaves many owners confused (and slightly embarrassed). The good news is that while it feels mysterious, there’s usually a perfectly sensible explanation, and in many cases, a simple solution. 

As a veterinary nurse and feline behaviour advisor I know first-hand that toileting issues can cause problems for many, but there are several reasons behind this rather odd but equally clever habit. Here’s how to ensure that a five-star toilet experience awaits their precious paws, rather than the inside of your bath.

Can cats smell the drain?

Many folks believe that cats go to the toilet in the bath simply because they can detect sewage smells rising from the drain. With their powerful noses, it’s easy to believe they might simply follow their instincts “that’s where waste goes”. It sounds plausible, but there’s actually no real evidence to support this theory. 

Modern plumbing systems are specifically designed to prevent sewer gases travelling back up the pipes. The U bend we now see beneath sinks, toilets and bathtubs blocks the odours from escaping preventing us from smelling them too. So most likely this myth is just coincidence and the reality is usually much more practical. 

Why is my cat using the bath as a toilet?

Cats are notoriously fussy about where they go to the toilet and why shouldn’t they be? How many of us humans would rather avoid a Portaloo for the fear of what mess may await or public toilets that don’t lock? When they choose to abandon the litter tray they’re usually responding to something about their environment that doesn’t quite suit them. 

So let’s look at why they may be choosing the bathtub rather than the litter trays we are providing them.

The bathtub looks like a litter tray (to your cat)

A bathtub can tick several boxes cats look for when seeking somewhere ideal to toilet.

• Smooth surface – it’s easy on their paws.

• Cool temperature – can be appealing in a warmer home or if they are experiencing pain whilst toileting. 

• High sides – gives them a sense of security.

• Privacy – bathrooms are often quiet spaces with limited footfall.

If their actual litter tray isn’t ticking the boxes the bath may simply seem like the better option. 

A dirty litter tray is driving your cat to the bath

Cleanliness is a major factor in feline toileting habits. Cats are naturally fastidious and many will refuse to use a tray that’s even slightly dirty. If waste has built up, or if the tray smells strongly of ammonia, your cat may look for a cleaner alternative, like the pristine white bathtub.  Even if the tray is scooped out daily some cats may still reject it expecting a spotless toilet. 

The wrong litter could be the issue

Cats can be surprisingly picky about texture and rightly so their paws are sensitive. Consider the type of litter you use as common complaints include:

• Litter that feels too sharp or hard.

• Strongly scented litter that’s too much for their sensitive noses.

• Sudden changes to their current type which causes confusion.

• Litter that doesn’t absorb well as they hate standing on already soiled areas.

If your cat dislikes the feel of their litter they may choose the bath’s smooth surface instead. 

The tray is in the wrong place

Location matters more than many owners realise and so considering where to place your litter trays is vital. They generally like their toilet area to be:

• Quiet.

• Private.

• Away from their food and water bowls.

• Free from sudden disturbances.

A tray placed next to a noisy washing machine, in a busy hallway or somewhere where another pet may ambush them can easily drive a cat to seek a calmer alternative. Bathrooms give them a quiet, enclosed space making the bath tub particularly attractive. 

There aren’t enough litter trays

In multi-cat households, litter tray numbers are one of the most common causes of toilet problems. The general rule recommended by behaviourists is: one litter tray per cat, plus one extra.

So if you have two cats, you should ideally have three trays. It is also best to ensure there is access to a tray on every level of the house. This is especially important if you have older cats or ones that suffer from joint problems. It is also advised to provide a safe option inside even if your cat goes outside. 

Without enough options, some cats look for additional ‘facilities’ and the bath might be one of them. 

Stress or territory anxiety can cause cats to toilet outside their litter tray

Cats are clever and can communicate stress through changes in their toileting behaviours. Triggers can include:

• Moving house.

• A new pet or baby.

• Outdoor cats appearing near windows.

• Changes to routine.

• Conflict between other cats in the house.

Toileting in unusual places can be a sign a cat is feeling insecure about their territory. It’s worth paying attention to this.

Bathrooms sometimes become chosen spots because they’re quieter and feel safer. 

Your cat could have medical issues

Sometimes the issue isn’t behaviour related at all. Conditions such as urinary tract infections (UTIs), bladder inflammation, or digestive problems can make cats feel an urgent need to go, wherever they happen to be. Sadly when this happens they may not make it to the litter tray in time. 

Litter tray checklist: how to get the setup right

If your cat has started using the bath, reviewing your litter tray setup is the best place to start.

Number of trays

• Follow the ‘one per cat plus one’ rule.

Placement

• Put trays in quiet, low-traffic areas.

• Avoid placing them next to food bowls.

• Keep them away from loud appliances.

Cleaning routine

• Scoop waste at least once daily.

• Fully change litter and wash the tray regularly.

Tray style

• Some cats dislike covered trays which can trap smells and limit escape routes.

• Others prefer them for privacy so it may take trial and error.

Tray size

• The tray should be large enough for your cat to turn around comfortably.

Litter choice

• Unscented, fine-grained, clumping litter is often best accepted.

How to stop your cat toileting in the bath

Once you’ve addressed the litter tray setup, you can gently discourage the bath from becoming a habit.

So try these to stop the problem:

• Keep the bathroom door closed when possible.

• Rinse the bath thoroughly to remove scent cues.

• Place a temporary litter tray in the bathroom to redirect the behaviour.

• Use a bath mat or towel in the tub as cats may dislike the unstable surface.

The key is to make the litter tray the more appealing choice.

When should you see a vet about your cat’s toileting?

If bath toileting starts suddenly, persists despite improving the litter tray setup, or comes with any signs of discomfort it’s important to rule out medical causes.

A vet visit is important if your cat:

• Is urinating more frequently.

• Appears to strain or cry while toileting.

• Has blood in their urine.

• Is excessively licking  the genital area.

• Stops using the litter tray entirely.

• Seems lethargic or unwell.

Urinary problems in cats can become serious quickly, so it’s always better to check if you are at all concerned.

The bottom line: why is my cat toileting in the bath?

While discovering your cat has used the bathtub as a toilet can be unpleasant it’s rarely mysterious or malicious, it’s usually their way of voting with their paws. Something about the current setup isn’t quite right, and the bathtub simply happens to tick more of their boxes. With a few tweaks to litter tray management and a quick vet check if anything seems off, most cats happily return to their designated facilities. 

Until then, take comfort in knowing you’re not the only one occasionally rinsing out the tub before your morning shower.

Resources

Grigg, Emma K., et al. “Litter Box Preference in Domestic Cats: Covered versus Uncovered.” Journal of Feline Medicine and Surgery, vol. 15, no. 4, Oct. 2012, pp. 280–84, https://doi.org/10.1177/1098612x12465606.

Guy, Norma C., et al. “Litterbox Size Preference in Domestic Cats (Felis Catus).” Journal of Veterinary Behavior, vol. 9, no. 2, Mar. 2014, pp. 78–82, https://doi.org/10.1016/j.jveb.2013.11.001.

Horwitz, Debra F. “Behavioral and Environmental Factors Associated with Elimination Behavior Problems in Cats: A Retrospective Study.” Applied Animal Behaviour Science, vol. 52, no. 1-2, Mar. 1997, pp. 129–37, https://doi.org/10.1016/s0168-1591(96)01073-8.