Why does my cat keep getting into cat fights? 

If you’ve ever been woken by the sound of hissing, yowling, and fur flying outside your window, you’ll know how distressing cat fights can be – for cats and their owners alike. Many cat owners find themselves wondering: why does my cat keep getting into fights, and what can I do to stop it? 

As a vet, I often see the aftermath of these encounters – torn ears, abscesses, infected wounds, and sometimes serious injuries. Beyond the physical harm, frequent fighting can cause severe stress for cats, affecting their health and wellbeing.  

Let’s explore why cats fight, the risks involved, and how you can protect your feline friend. 

Are cats aggressive by nature? 

Although cats can appear fierce during a fight, it’s important to understand that they don’t pick fights for the sake of it. Cats aren’t naturally aggressive; most aggression has a purpose, and it usually stems from feelings of self-preservation rather than malice.  

Cats are solitary hunters by nature, which means they rely on being healthy and uninjured to survive. In the wild, unnecessary fights risk injury, which can reduce a cat’s ability to hunt and protect itself. For this reason, cats prefer to avoid physical conflict whenever possible. They send messages to each other using scent marking, to warn other cats away and to avoid meeting each other in person. They also use a range of body language to communicate their feelings, to avoid the situation escalating to a physical fight, such as: 

Most confrontations stop at this stage – but when both cats feel they can’t back down (or don’t understand each other’s signals), a physical battle may begin.  

Why do fights happen? 

There are several common reasons cats end up in conflict: 

1. Territory and space 

Cats are territorial animals. They prefer to have a core area they feel safe in, where they eat, sleep and play, and a wider area they patrol. When another cat intrudes – whether it’s a neighbour’s cat, a stray, or even another cat from the same household – tension can boil over into a fight. This is especially common in urban areas where many cats share overlapping territories. Even two cats from the same household cat fight if they feel they don’t have enough space or resources indoors. 

2. Hormones and mating 

Unneutered cats are the most likely culprits in regular fighting. Entire males roam widely in search of mates and are willing to battle other males for access to females. Females in heat may also become vocal and defensive, attracting unwanted advances and sparking fights between competing males. 

Neutering is one of the single most effective ways to reduce fighting, roaming, and territorial aggression. It’s also vital for reducing unwanted litters and protecting cats from reproductive cancers and infections. The best time to neuter your cat is at around four months of age, before they come into season. 

3. Fear and defensive behaviour 

Not all fights are about territory or mating. Sometimes cats fight because they feel threatened. An anxious or shy cat might lash out defensively if cornered by a more confident cat. Over time, repeated stressful encounters can make a cat become stressed and hyper-vigilant and more likely to react aggressively.  

4. Poor socialisation 

Cats that weren’t well socialised as kittens may not ‘speak cat’ fluently and they may be less tolerant of other cats. They might not recognise or respect the body language of other cats leading to misunderstandings and conflicts may escalate more quickly. 

Why are cat fights a welfare issue? 

Fighting is not just a noisy nuisance – it has serious consequences for a cat’s welfare and health. 

1. Injuries and infections 

Cat bites easily puncture the skin, introducing bacteria deep under the surface. This often results in abscesses – painful swellings filled with pus – which usually need veterinary treatment. This might involve draining and sometimes antibiotics or surgery. Untreated bite wounds can make cats very unwell, with high temperatures and systemic infections. 

Fighting also spreads serious diseases such as Feline Immunodeficiency Virus (FIV) and Feline Leukaemia Virus (FeLV). Both viruses are transmitted through bite wounds and can have lifelong impacts on a cat’s health. 

2. Chronic stress 

Even if your cat isn’t physically injured, repeated conflicts or the constant threat of attack can cause stress. Stress affects cats in subtle but serious ways. It takes its toll on the body by suppressing a cat’s immune system, leading to issues like urinary cystitis, poor appetite and overgrooming. Chronic stress can also change a cat’s behaviour, making them more likely to spend time hiding or showing signs of aggression at home. 

3. Risk of road accidents 

Cats that roam widely to fight or patrol their territory are at greater risk of being hit by cars. This is particularly true for unneutered males, who may travel significant distances; but it can also apply to any cat, fleeing a fight they don’t want to be involved in. 

How can you reduce or prevent cat fights? 

Thankfully, there are steps you can take to protect your cat from the risks of fighting and keep your household more peaceful. 

1. Neuter your cat 

This is the single most effective step you can take. Neutering reduces roaming, territorial marking, and aggression. It also has health benefits, such as lowering the risk of certain cancers and infections. The best time to neuter cats is when they are four months old. If your cat isn’t already neutered, speak to your vet about arranging the procedure. 

2. Manage outdoor access 

If your cat frequently comes home with scratches or wounds, consider supervised outdoor time or building a “catio” (an enclosed outdoor space). Keeping your cat indoors during peak fighting times – often dusk and dawn – can also help. 

Making the indoor environment more appealing can help too. Climbing trees, scratching posts, toys, and puzzle feeders help cats stay mentally stimulated indoors. 

3. Reduce outdoor tension 

If you know which local cats your pet is clashing with, talk to the other owners. You may be able to agree on staggered outdoor times or other measures to reduce overlap. 

You can also deter intruding cats from entering your garden using humane deterrents, such as motion-activated sprinklers, citrus scents, or fencing designed to keep cats out. Microchip-activated cat flaps can help prevent other cats coming into your cat’s home. 

4. Address stress at home 

If you have multiple cats, ensure your home has plenty of resources – litter trays, food and water stations, scratching posts, and high resting places. Think “one per cat, plus one extra” so that each cat has good access to these resources. Competition for these resources can spark tension even between housemates. 

Using pheromone diffusers (such as Feliway) can also help to calm anxious cats and reduce aggressive behaviours. 

5. Treat injuries promptly 

Even minor wounds can turn serious if left untreated. If your cat comes home limping, with swelling, or seems off-colour, see your vet as soon as possible. They can clean wounds, prescribe pain relief and check for infections. 

6. Recognise stress early 

Subtle signs your cat is struggling include hiding more, overgrooming, spraying, toileting outside of the litter tray, changes in appetite, or avoiding certain rooms or outdoor areas. These might signal that your cat is in conflict with another cat in their territory, or at least perceives a threat, and that this is affecting their wellbeing.  

When to see your vet about cat fights 

If your cat is fighting regularly, your vet can help in several ways: 

Protecting your cat’s welfare 

Fighting isn’t just “part of being a cat” – it can have lasting impacts on their health and wellbeing. By neutering, managing their environment, reducing triggers, and seeking veterinary advice when needed, you can help your cat feel safe and secure – with far fewer battles on the streets.   

Further reading

Conflict between cats – iCatCare

When cats attack – Cats Protection