Cat neutering - a guide to castration and spaying


  • ‘Neutering’ is an operation to remove testicles or ovaries. For males it’s called castration, and for females it’s called spaying.
  • Neutering has many benefits – as well as preventing pregnancy, it also reduces the chance of your cat getting into a fight, roaming away from home and catching diseases such as FIV.
  • Most cats can be neutered at 4 months old.
  • We advise keeping your cat indoors until they have been neutered, vaccinated and microchipped.

Reasons to have your cat neutered

We recommend that all cats are neutered at around 4 months old. Neutering has many benefits, including:

Female cats

  • Prevents pregnancies
  • Stops seasons/coming on heat
  • Prevents cancer of the ovaries and uterus
  • Prevents pyometra (womb infection)

Male cats

  • Reduces roaming away from home
  • Reduces the chance of being hit by a car
  • Reduces fighting and aggression
  • Reduces the chance of contracting Feline Immunodeficiency Virus (FIV)
  • Prevents testicular cancer
  • Weakens the smell of their urine

When to have your cat neutered

We advise that all cats are neutered at 4 months old, unless your vet advises otherwise. Your vet might want to wait a bit longer if your kitten is particularly small for their age, or if they have been/are unwell.

What will happen when my cat is neutered?

The night before

  • It’s important to starve your cat for 6-8 hours before their operation – this is to make sure their stomach is empty and they don’t regurgitate/choke under anaesthetic. It’s fine for them to have their dinner the night before, but make sure you don’t give them any food/treats after about 10pm, and certainly no breakfast.
  • Water is fine overnight – you’ll just need to take it away at around 6-7am the morning of their surgery.
  • It’s best to keep your cat indoors overnight to make sure they don’t get any food elsewhere!

The operation

  • Your vet will check your cat over on the morning of their operation, and ask you a few questions about their general health – if your cat has any existing conditions, or problems in the days leading up to their operation, it’s important to let your vet know.
  • Once your cat is admitted into the hospital they will be settled in a warm, comfortable bed, and given a light sedative to relax them ready for their anaesthetic.
  • Once the sedative has taken affect, your cat will be given a full/general anaesthetic and pain relief. Their surgery site will be clipped and cleaned, and they will be carefully monitored while they have their operation.
  • Males/castration – a small cut is made in the scrotum over each testicle so that they can be tied off and removed. Stitches aren’t usually necessary because the cuts are so small that they tend to heal very quickly on their own.
  • Females – a small cut is made into the abdomen (tummy) so the ovaries and womb can be carefully tied off and removed. The abdomen is then stitched up layer by layer – you may or may not be able to see the final layer of skin stitches, depending on which type your vet uses. Cat spays are usually done through the flank (side), but in some cases they can be done ‘midline’ (the same as a dog spay).
  • Cryptorchid males – if your cat is cryptorchid, meaning one or both of their testicles aren’t in their scrotum (ball sack), their castration will take a bit longer than usual because your vet will need to find their missing testicle(s). It’s especially important to have cryptorchid cats neutered because retained testicles are more likely to become cancerous and can sometimes twist round, which is extremely painful and potentially life threatening.


  • Your cat will wake from their anaesthetic under careful watch, and be placed in a warm, comfortable bed to recover.
  • Most cats can return home a few hours after their operation.

Recovery, home care and check-ups


  • When your cat comes home they are likely to be sleepy and disorientated until the anaesthetic drugs start to wear-off (which usually takes 12-48 hours).
  • It’s important to try to keep them as quiet as possible, even once the anaesthetic drugs have worn off. This is especially important for female cats because their internal stitches might loosen if they become very lively.
  • If necessary, you may need to confine your cat to one room for a few days to keep them as quiet as possible.

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. Alternatives include soft buster collars and body suits.


  • Female cats usually need to be checked 2-3 days, and 7-10 days after their operation to make sure they are healing as expected.
  • Male cats tend to only have one check-up afterwards, or they may not need one at all if they are doing well.
  • If you have any concerns in the meanwhile, always call you vet for advice.

Stitch removal

  • Most male cats don’t have stitches when they are castrated because the wounds are very small and tend to heal quicker without.
  • If you have a female cat, she may or may not need stitches removing depending the type your vet used. Dissolvable stitches (usually blue/purple coloured) don’t need to be removed. Non-dissolvable stitches need to be removed 7-14 days after their operation.

Going outdoors

  • Male cats can go outside as soon as their wounds have healed over.
  • Females need to be rested for approximately 10-14 days before being allowed outside.

Complications of neutering

There are always risks and potential for complications during an operation, however, neutering is a routine procedure that is generally considered very safe. Always speak to your vet if you are concerned about operation risks.

Cat neutering cost

The cost of neutering varies between vet practices – call your vet practice for exact prices. If you are struggling with the cost, ask your vet practice about any charity help that’s available.

Keeping unneutered cats safe

It’s essential to keep your cat indoors until they are neutered. Unneutered cats can get pregnant from as young as four months old, are at a high risk of getting into cat fights, roaming, being hit by a car and catching diseases such as Feline Immunodeficiency Virus (FIV). If you have an unneutered male and female cat, you’ll need to keep them apart after they turn 4 months old, even if they are related. Check out our guide to keeping indoor cats happy and entertained.


Will my cat need to wear a buster collar after being neutered?

Most female cats need to wear a buster collar or medical shirt to protect their wound after being neutered. Male cats only tend to need one if they are licking their wound a lot. If your cat repeatedly licks or damages their wound it may become infected or breakdown.

Should my cat have a litter before I neuter her?

No, having kittens before being spayed won’t benefit your cat. 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. 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.

Can you spay a cat while they are in season?

Yes, unlike dogs, cats can be spayed while they’re on heat. It’s slightly more risky because blood vessels around their womb tend to be a bit bigger, but it’s a procedure that’s done regularly by most vets.

I am a PDSA client, how do I get my cat neutered?

We face a huge demand for our services at PDSA, and although our priority is urgent and lifesaving treatment, wherever possible we also provide preventive services such as neutering. To find out whether your local PDSA is offering neutering visit our eligibility checker. If your local PDSA is unable to offer neutering at present, we recommend that you try another local vet practice. Don’t worry, if you are registered with PDSA client and have your cat neutered elsewhere, you will stay registered with us should they become unwell at any point.

Can my cat go outside before he/she is neutered?

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

Will neutering make my cat fat?

Due to the hormonal changes afterwards, your cat will need approximately 25% less calories once they have been spayed or castrated. We recommend that you reduce their portion sizes, or feed them a food specifically for neutered cats, which is naturally lower in calories. If you’re struggling to keep them slim, speak to your vet or vet nurse about the best ways to keep them at an ideal body condition score.

Does my indoor cat need to be neutered?

Yes, neutering isn’t just about stopping your cat from having babies – it has a whole host of benefits. Spaying your female cat will prevent her from coming into season, which can be quite stressful in a home environment, prevent her developing a pyometra (a serious womb infection), and prevent mammary, ovarian or uterine (womb) cancer. Castrating your male cat will reduce the chance of them spraying around the house, and lower their chance of prostate disease later in life.

Will castration stop my cat spraying?

Castration reduces the chance of a male cat spraying to mark their territory, but they may still do it if they are stressed or unsettled. 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.

Should I get my cat microchipped at the same time as being 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.

Why does my cat still look like they have testicles after being castrated?

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 spay 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, ideally most cats should be neutered at 4 months old, before their first season.

I have a female and male cat, 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.

Will cat siblings mate?

Cats aren’t selective about who they mate with, and given the opportunity will mate with their siblings. If your cats accidentally mate and they’re related, contact your vet as soon as possible – or better still get them neutered before any accidents happen.

Published: March 2022

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