Cat neutering - a guide to castration and spaying


  • ‘Neutering’ is an operation to remove the testicles or ovaries from a cat.
    • Castration = removing testicles
    • Speying = removing ovaries (and usually womb)
  • Neutering is a routine procedure, performed by most vets on a daily basis.
  • Most cats should be neutered at 4 months old, and unneutered cats should not be allowed to roam freely outdoors.
  • Neutering your cat helps to prevent unwanted pregnancies and the spread of diseases such as FIV and FeLV.

General information

Neutering has many different names: castration, speying, ‘the snip’, ‘being done’, ‘being dressed’, all meaning the same thing, an operation to remove the testicles or ovaries. Castration is specific to male cats (means removing testicles), and speying is specific to female cats (means removing the ovaries and usually the womb). Neutering prevents unwanted pregnancies, prevents certain diseases and provides a number of health benefits.

Reasons to have your cat neutered

Some of the benefits of neutering include:

Female cats

  • Prevents unwanted pregnancies
  • Prevents ovarian and uterine cancers
  • Prevents pyometra (life-threatening womb infections)
  • Reduces the chance of unwanted behaviours related to hormones (such as aggression)
  • Stops seasons/ coming on heat

Male cats

  • Prevents testicular cancer
  • Reduces territorial fighting and chances of getting FIV (Feline AIDs)
  • Reduces the urge to find female cats, so less roaming and lower chance of being hit by a car or going missing
  • Reduces the smell of urine
  • Reduces the chance of unwanted behaviours related to hormones (such as aggression)

When to have your cat neutered

Most cats (both males and females), can be neutered from 4 months old. Neutering at this age has many benefits, especially for female cats, however, it’s always important to discuss the decision with your vet because exact timings should be based on a number of different factors, including:

  • Weight: The risk of anaesthetic can be slightly higher in small kittens, so your vet may recommend waiting until your cat is a certain weight before they are neutered. It’s also important they are healthy shape because overweight cats have a higher anaesthetic risk and more chance of complications during surgery.
  • Other health conditions: if your cat is suffering from another health condition it may change their ideal neutering time.

The procedure


  • Food and water - don’t feed your cat anything for 6-8 hours before their operation to make sure their stomach is empty (so they don’t regurgitate and choke under anaesthetic). This means no breakfast and no treats. Water is fine until 2-3 hours before their operation (i.e. take it away at 6-7am the morning of their surgery). It’s also best to keep them indoors overnight (if they have access outdoors), to make sure they don’t eat anything elsewhere.
  • Health - let your vet know if your cat has any health problems, or if you’ve been concerned about them in the days leading up to their operation.

Before the procedure

Your vet will check your cat over, settle them in a warm, comfortable bed and give them a light sedative to relax and prepare them for their anaesthetic.

The operation

Your cat will be put under a full/general anaesthetic, their surgery site will be clipped and cleaned, and they will be given pain relief. They will then be carefully monitored while they have their operation:

  • Males – two small incision are made on the scrotum so each testicle can be tied off and removed. Your cat won’t usually have any stitches in their wound. If your cat is cryptorchid (one or both testicles haven’t dropped), their operation will often be more complicated. It’s especially important to have cryptorchid cats neutered because retained testicles can twist round or even become cancerous.
  • Females - an incision is made into the abdomen (tummy), so the ovaries and womb can be carefully tied off (with dissolvable stitches) and removed. The surgery is usually performed on your cat's flank (side) but in some cases can be midline (under your cat’s belly). Their wound will be closed in a few separate layers and you may or may not be able to see the stitches from the outside depending on the type your vet uses.

After the procedure

Your cat will wake from their anaesthetic under careful watch, and then placed in a warm, comfortable bed to recover. Most cats can return home a few hours after their operation, but some need to be monitored for longer.

Recovery, home care and check-ups


When your cat comes home from their operation, they might be a bit sleepy and disorientated. This can last for several hours, but they will start to feel much better as the anaesthetic drugs wear-off (usually within 24-48 hours). Once your cat is feeling brighter and more energetic, it’s likely that they will want to run around as normal, but it’s important that they rest for 7-10 days to prevent any complications. If necessary, you may need to confine them to one room and make sure there is no furniture for them to jump on.

Protecting the wound

It’s likely that your cat will be given a protective cone/buster collar to stop them licking and nibbling at their wound. Speak to your vet beforehand if you would like a soft buster collar or a body suit for you cat.


Male cats often only have one check-up, or may not need a check-up at all if they are doing well. Female cats often need to be checked 2-3 days and 7-10 days after their operation to make sure they are healing and feeling well. Talk to your vet if you have any concerns about your cat after their operation.

Stitch removal

Most male cats don’t have stitches when they are castrated because the wounds are so small that they heal by themselves (like a small cut). Female cats, may or may not need stitches removing depending whether your vet used dissolvable stitches (usually blue/purple coloured). Non-dissolvable stitches will need to be removed 7-14 days after their operation.

Going outdoors

Male cats can go back outside and return to full exercise as soon as their wounds have healed over. Females need to be rested for a little longer and should be rested for approximately 10-14 days before being allowed back outside.


Neutering is a relatively safe, routine procedure, performed by most vets on a daily basis. However, like any operation there are always risks and the potential for complications during and after the surgery. Speak to your vet if you are concerned.

Cat neutering cost

It’s impossible to say exactly how much neutering your cat will cost because prices vary between practices. If you phone your vets, they will be able to tell you their prices.

If you are struggling with the cost of neutering your cat, speak to your vet practice or your local cat warden about any charity help that is available.


Can my cat go outside before they’re neutered?

No, your cat should not go outside until they’ve been neutered (and microchipped/vaccinated).

Should I get my cat microchipped when they are neutered?

Yes, it’s a good idea to get your cat microchipped at the same time as being neutered because they will be under anaesthetic and won’t feel the microchipping needle.

Should my cat have a litter before I neuter her?

No, there is no evidence to show that having a litter of kittens benefits cats. Pregnancy/giving birth can come with complications and looking after a litter of kittens is hard work, expensive, and time-consuming - certainly not something to enter into without a great deal of thought and planning. If you want to breed from your cat, its best speak to your vet for advice to find out how you can do it responsibly and safely.

Will neutering make my cat fat?

No, neutering your cat won’t make them fat. However, afterwards, your cat may not need as many calories to maintain a healthy weight. Make sure your cat is fed an appropriate amount of a complete diet that’s right for their life stage so they stay slim and healthy. In fact, you can buy special food for neutered cats, which have the correct balance of nutrients and calories for them. If you’re concerned your cat is putting on weight after neutering, talk to your vet or vet nurse about the best ways to keep them an ideal body condition score.

Can you spey a cat in heat?

Yes, although speying a cat in heat isn’t quite as simple as a routine spey, it’s done regularly by most vets. Speying during a heat is a little more risky is because the blood vessels around their womb tend to be a bit larger and more likely to bleed. This means the operation is slightly more risky and can take a little longer.  

Does my cat need to wear a buster collar?

Yes, most cats need to wear a buster collar or medical shirt to protect their wound after being neutered. If your cat licks or damages their wound they may cause it to breakdown or become infected.

Do male cats spray after being neutered?

There are many reasons why cats spray; sometimes because of hormones, but more commonly due to stress. If your cat has suddenly started spraying, speak to your vet to discuss whether neutering might help. Find out more in our article about urine problems in cats.

Why does my neutered cat still look like they have testicles (balls)?

When a cat is castrated, the testicles are removed but the scrotum (ball sack) isn’t. This means sometimes they look like they still have testicles after their operation. Over time the scrotum will shrink and become less noticeable. If you notice swelling or redness in your cat’s scrotum after their surgery, contact your vet for advice.

I have an unneutered older cat, is it too late to neuter them?

No, many people worry about neutering older pets, but in most cases it’s still a very safe and worthwhile operation, regardless of age. 

I’m worried my cat is pregnant, can she still be neutered?

Yes, in most cases it’s possible to spey a pregnant cat. If you think your cat might be pregnant, contact your vet as soon as possible to discuss your options.

Can I neuter before my cat’s first season?

Yes, it’s ideal for most cats to be neutered at 4 months old, before their first season.

I have unneutered female and male cats in my household, what should I do to avoid unwanted pregnancies?

If you have an unneutered male and female in the same household, have them neutered as soon as they reach 4 months old. If this isn’t possible, and your female cat comes on heat, it’s essential to keep your cats apart at all times to stop them from mating. Please remember that related cats will mate, including brothers, sisters, fathers and daughters.

Published: October 2020

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Written by vets and vet nurses. This advice is for UK pets only.

Illustrations by Samantha Elmhurst