Cat neutering

31 May 2023

Neutering is a simple operation that will stop unwanted pregnancies and benefit your cat’s overall health and wellbeing.

Cat sitting on a wooden floor

When should my cat be neutered?

Providing there is no medical reason not to, the best time to neuter your kitten is at four months of age, before they start to become sexually mature.

For more information or to find a vet, please visit the kitten neutering database.

Benefits of neutering – why should my cat be neutered?

Health and welfare

When in season, unneutered cats will have much more physical strain put on their bodies than neutered cats. This is due to the changes in their hormones, increased activity and restlessness, and for females the process of producing and looking after a litter of kittens.

Unneutered female cats are more likely to suffer from pyometria (an infection in their womb) and cancers of the ovaries, uterus and mammary glands later in life.

Unneutered females are more likely to contract serious life-threatening diseases (such as FIV), which can be passed on via the infected saliva of a male cat when he bites her neck during mating.

If the mother is sick, she can pass on her illnesses to the kittens, making them sick too. These illnesses may include:

  • Cat Flu – in young kittens this can lead to loss of eyesight or severe damage to their eyes and even death from secondary infections caused by the flu.
  • Feline immunodeficiency virus (FIV)FIV is an incurable disease which affects the cat's immune system and can lead to long-term negative impacts on their health.
  • Feline leukaemia virus (FeLV) – like leukaemia in humans, this virus can significantly increase the risk of cats developing anaemia, immunosuppression and also cancer. An estimated 80-90% of cats infected with FeLV die within 3-4 years of being diagnosed with the disease.
  • Feline infectious enteritis (FIE) – this virus causes severe gastroenteritis and, in infected kittens, can often lead to death. Pregnant females who are infected with FIE, the virus can spread to her unborn kittens, causing them permanent brain damage.

Unneutered males are more likely to get in to fights with other cats, also putting them at greater risk of contracting the same life-threatening diseases as females. Increased fighting may also increase their risk of serious physical injury.


When in season, unneutered females are likely to go outside more, seeking mates. Unneutered males are also likely to go outside and roam a lot further from home than usual. For both sexes, this may potentially put them in harm’s way of busy roads and other hazards they would normally otherwise avoid.

The changes in the hormones of unneutered cats when in season may lead to increased restlessness, general stress and arousal, a decreased ability to relax and potential changes in the cat's behaviour towards humans.

Unneutered cats may be more likely to spray indoors and outdoors.

If your cat is used to going outside and you keep them inside while they are in season to avoid unwanted kittens, this may lead to a significant compromise to their welfare, leading to a very stressed, frustrated and unhappy cat who is desperate to go outdoors.


Females with kittens to feed are more likely to actively hunt and disturb wildlife.

Unneutered females may be very vocal and will attract unneutered toms to an area which could then be very disturbing and stressful for other neighbourhood cats, as well as a nuisance to local residents.

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How much does it cost?

It is usually slightly more expensive to neuter female than male cats, however help with costs is available. If you rehome a cat from a rehoming centre, they should already be neutered, and this cost will be incorporated into the adoption fee.

There are various schemes across the UK which provide financial support to owners wanting to neuter their cats such as Cats Protection, Blue Cross, The Mayhew Animal Home and RSPCA.

Where can I get my cat neutered?

It is very easy to find a vet that is able to perform neutering at four months of age using the kitten neutering database.

Dispelling the myths surrounding neutering

There is currently no evidence to suggest that there are any negative long-term effects on either the behaviour or development of neutering kittens as young as eight weeks. Neutering kittens from four months, or younger in some cases, is now becoming much more common among vets while advances in surgical techniques and better drugs mean that there are no longer the same concerns over earlier neutering as there used to be. If performed by a veterinary surgeon who has experience of carrying out kitten neutering, the procedure can actually be less invasive, quicker and safer to perform than when done on older cats. Cats neutered earlier may generally also have a quicker recovery rate than older cats.

There are no documented health benefits associated with this. Young mothers are at greater risk of complications during the delivery of their kittens.

Female cats can start to become sexually mature from as early as four months of age, so in effect, kittens can have kittens of their own. It is therefore important that your cat is neutered before they can go outside, even if they are a young kitten.

Cats don’t actively decide to have kittens – their hormones will drive them to pursue and mate with other cats, but they are not necessarily aware of the consequences of their actions. Allowing a cat to mate puts their ability to live a life free from disease and ill health at risk. Making a kitten or young cat have kittens also takes away their ability to grow and develop unhindered and without the stress of having to look after other cats.

Cats will mate with their closest relatives (i.e. brother and sister, mother and son, father and daughter) so neutering all cats who are going to come in contact with each other (whether related or unrelated) is very important. Kittens born from closely-related parents may also be more likely to suffer from genetic defects which would negatively affect their health.

Your unneutered male cat could be responsible for impregnating many unneutered female cats that you never see. These may be people’s pets or stray cats. Either way, he is contributing to an increase in the population of kittens – many of whom may not always be wanted and may struggle to find loving homes. Kittens born to stray females may also be at a greater risk of suffering from disease or infection.

The length of pregnancy in cats is just nine weeks and a female cat can often come into season again just six weeks after giving birth. A female cat can easily have as many as three litters of kittens a year – that’s potentially up to eighteen kittens in any one year. Estimates suggest that a single unneutered female cat and the subsequent offspring she produces can actually be responsible for around 20,000 other cats in just five years.

Even at each of these stages it may still be possible and safe to neuter your cat. You can contact your vet for further advice on this.

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