When you have more than one cat in your house, it's a good idea to have more than one litter box. Many people choose to have multiple litter boxes (commonly one per cat plus one extra) because it makes cleaning up poop an easier and less frequent job, but that's not the only reason it's a good idea. Multiple litter boxes in the household is also healthier for your clowder of cats. Here are 3 reasons why.
Constipation and UTIs
You may have already noticed that the cats in your home have an unwritten hierarchy. Generally, one cat will be more dominant than the rest, taking an alpha position. This cat can be bossy, territorial, and even aggressive to the rest of your cats, and such behaviour can extend to toileting. The alpha cat may become territorial over a litter box and refuse to let the other cats use it. If you don't have another litter box, the cat who's being blocked will be forced to hold in their waste. This can lead to two main problems: constipation (from holding in faeces) or a urinary tract problem like an infection (from holding in urine). If left to get worse, constipation and UTIs can lead to serious problems for the gastointestinal and renal systems, so it's important that every cat always has access to a litter box.
Stress and Aggression
As mentioned above, cats tend to form hierarchies. This is because, unlike dogs, they are naturally solitary animals. Cats like to have their own space and alone time, and like humans, they don't always want to share the bathroom with someone else. Litter box overcrowding can be upsetting and stressful for cats looking for a little isolation. Stress can lead to a whole host of health problems, from loss of appetite to diarrhoea to compulsive scratching. It can also cause your cats to become aggressive towards each other, which can lead to harmful fights. A cat should always be able to have his own space to urinate and defecate to prevent such stress and aggression.
Spread of Disease
The only thing worse than having one sick cat is having multiple sick cats. Often, it's difficult to prevent the spread of contagious diseases and illnesses between cats who live in the same house, but the risk can be reduced by making sure each cat can have its own litter box. If one cat is forced to do their business in the same box as every other cat, they're a lot more likely to pick up infections or parasites that can be transferred through waste.
Remember, if you do notice your cat showing any signs of constipation, infection, illness, or stress, the best thing to do is take them to an animal hospital. Your vet can advise you on whether too few litter boxes could be a factor and let you know other ways to keep multiple cats happy and healthy in the same household.