Skip to content

Cats and Inappropriate Urination – Why it Happens and What to Do

Cats and Inappropriate Urination – Why it Happens and What to Do
by Dr Caity Venniker

Read time: 5 min

At KatKin, we like to think outside the box, but we prefer that everything else happens inside the box! Inappropriate urination is one of the most common behaviour issues reported by cat owners. It can occur for a multitude of reasons, including medical problems, litter tray aversion, or as a means of scent marking. Ascertaining the underlying cause is important so that you can manage the problem appropriately.

Medical Reasons for House Soiling

If your cat starts to urinate outside of the litter tray, it is important to have them checked by your vet as there are a multitude of medical reasons which may be causing the unwanted behaviour. Inappropriate urination can be a red flag for the following conditions:

  • Kidney failure, thyroid problems and diabetes are all associated with increased drinking. This can lead to a more frequent and urgent need to urinate, which can result in accidents.

  • Bladder infections, inflammation, or cancer, as well as bladder or kidney stones can make urination more frequent, and also painful. Some cats associate the discomfort with the litter tray and then avoid using it.

Arthritis can also play a role, in that arthritic cats may be unable to reach the tray in time, or have difficulty getting into it.

Litter Tray Aversion

Once any medical problems have been ruled out, it’s time to look at all the other possible reasons for your cat urinating in an inappropriate place. Firstly, make sure you have enough trays in the home – the same number of litter trays as the number of cats plus one.

Aversion to a litter tray can happen for a variety of reasons:

  • The litter box may either not be big enough, or the wrong type. Many cats prefer an open tray rather than a covered box, as covered boxes tend to hold odours inside. Covered boxes also allow cats to be ambushed by other cats if there is conflict within the home. Young or old cats may need a tray with lower sides to make it more easily accessible for them.

  • The location of the tray may be unfavourable to your cat. It may be too exposed such as near entrances or windows; or in an area that can be blocked off by other pets. It may be stressful for your cat if the tray is positioned next to a tumble drier or other noisy appliance. You can try positioning the tray where your cat has chosen to urinate and then gradually moving it to a more acceptable location.

  • The litter itself can be too shallow, too deep, or an unfavourable substrate. It is helpful to take note of where your cat is choosing to urinate as this may give an indication of what type of litter is preferred. For example, urine in a bathtub suggests that less litter is preferred, whereas soiled bedding or thick carpets suggest that deep litter is preferred. Often, problems arise when the litter is simply too dirty and needs to be changed more frequently. Some cats are very fastidious and will not tolerate more than one or two wet patches before they will seek other, cleaner areas. Certain behaviours can indicate that the litter is too dirty. These include your cat eliminating close to the tray; perching on the edge; or not burying their waste.

Urine Spraying

Urine spraying is quite different to normal urination. It occurs when a small amount of urine is deposited against a vertical surface, in order to mark the environment with scent. It can be used to establish or reinforce a boundary, or to alert other cats of an opportunity to mate. Cats will squat to urinate, but remain standing to spray, with their tails held upright.

Spraying is usually performed by unneutered males and, to a lesser extent, unspayed females, but it can occur in sterilised animals too. It is more common when territories are threatened, such as when a new cat arrives in the home or neighbourhood, or when many cats cohabit. It can also happen when new furniture is acquired to mark it, or even when cats feel frustrated or bored.

Now What? How to Deal with Inappropriate Urination

The management of inappropriate urination depends on the underlying cause. It’s important that you have your cat checked by a vet for any medical problems; and that you ascertain whether you are dealing with urination to void the bladder or spray marking.

The areas where the house has been soiled must be cleaned thoroughly, and the smell must be neutralised. Avoid cleaning products that contain ammonia or vinegar as these have a similar smell to urine and can confuse the issue. One effective method is to clean soiled areas with a 10% biological detergent and then spray the area with surgical spirit (1).

Urinating in a particular site can quickly become a habit so prompt action is necessary. You should not however use punishment. Inflicting fear, pain or stress may make the problem worse.

If your cat is spraying, it is advisable to spay or neuter them. Also try to reduce any possible stressors. You may need to control access to the property by outside cats; or, if cats within the home are fighting, try separating them for a while and reintroducing them slowly. Pheromone therapy can be very helpful for the management of urine spraying, as it not only helps to decrease stress but also acts as an alternative marker. If synthetic pheromones are applied daily where the cat has sprayed it can discourage the behaviour. Anti-anxiety medication may help; but should only be used in conjunction with environmental assessment and optimisation.

If your cat is urinating in an inappropriate place, first have them checked by a vet. If they are in good health, the next step is to assess the litter tray, litter and location of the tray; as well as the dynamic between cats in the home. You may need to experiment with different types of litter, tray and location. Clean the tray at least once per week; and remove soiled patches two or three times daily. It may be worth consulting a behaviour specialist if you are unable to resolve the issue.

Inappropriate urination is a common behavioural problem, and it can be frustrating and difficult to manage. It also, however, offers a window of insight into your cat’s health and psychological well-being, as well as feline dynamics within the home.

If your cat is urinating inappropriately and you would like any more advice, feel free to contact us at and we will try our best to help.


  1. Atkinson, T. (2018). Practical Feline Behaviour: Understanding Cat Behaviour and Improving Welfare. CAB International. Oxfordshire, UK.

Related articles