When to Neuter a Dog: The Best Age for Spaying and Castration in the UK

There is no single right age to neuter a dog. Updated guidance from the UK's main veterinary bodies now moves away from early neutering: for most female dogs it suggests spaying between 12 and 23 months, depending on breed, and for males it says castration is a case-by-case decision that should not happen before the dog is physically mature. Older charity advice still says many dogs can be neutered from around 6 months, so expect to hear a range. Your vet, who knows your dog's breed, size and temperament, makes the final call.

What is the best age to neuter a dog?

There is no best age that suits every dog. Blue Cross says there is limited evidence on the best timing and that it depends on your dog's breed, size, sex and temperament. The RSPCA simply says your vet will advise on the best time to neuter your pet, so talk to your vet before you book anything. What has changed is the direction of travel: in 2026 the British Veterinary Association (BVA) and the British Small Animal Veterinary Association (BSAVA) published a joint position that marks "a shift away from early neutering for both male and female dogs".

Neutering is one of the big routine health decisions of your dog's first two years, alongside your puppy's vaccinations and boosters. It is worth raising at your puppy's early vet visits, long before the decision to neuter is due.

The main UK veterinary and welfare sources do not all agree on timing, which is why the vet's view for individual dogs matters most.

What the latest BVA and BSAVA guidance says

The joint position replaces the old habit of early neutering at six months with a contextualised, case-by-case approach that weighs age, breed and lifestyle. The key points for dog owners are:

• Wait for maturity. Losing sex hormones can affect musculoskeletal development, so neutering should wait until the dog reaches maturity.
• Skeletal maturity varies. It arrives between 12 and 23 months depending on breed, with larger breeds maturing later.
• Very early neutering carries extra risk. Neutering before 6 months is linked to a higher risk of orthopaedic (bone and joint) conditions and possibly urinary incontinence in females.
• Females are a clearer case than males. The BVA recommends spaying female dogs in most cases because of the impact of unwanted litters, while the case for castrating males "is more complicated" and has no clear consensus.
• Breed and size matter. Longer-term health effects vary with breed, size and age at neutering, and the BVA says more research on common breeds is needed.

Some vet practices will still follow older protocols, and some charity advice pages predate this update. If your vet suggests a different age to neuter your dog, ask them why; there is often a good reason linked to your dog's breed or circumstances.

When to spay a female dog

For most bitches, the current veterinary guidance is to spay between 12 and 23 months of age, with the exact timing set by breed and expected age at maturity, unless she is intended for breeding. The main reasons are the health and welfare risks of pregnancy and whelping, and the risk of womb and ovarian disease later in life.

Before or after her first season?

• Spaying before the first season. PDSA says it is safe to neuter before her first season and that doing so lowers the risk of mammary cancer and pyometra (a womb infection). The Royal Kennel Club notes that some vets spay early for these reasons and to prevent an accidental pregnancy.
• Waiting until after one or more seasons. Other vets prefer to wait so that ovarian hormones can keep maturing the dog, which may lower the risk of some later conditions. This fits the BVA and BSAVA preference for spaying once a female is mature.

There is no known benefit to letting a female have a litter before she is spayed.

Timing around a season

Once she has had a season, PDSA advises waiting for approximately 3 months before she is spayed. Many vets avoid surgery while a female dog is in season, or while she shows signs of a false pregnancy in the weeks after a season. Note the date each season starts and tell your vet, along with any signs of false pregnancy.

Most dogs have two seasons a year, each lasting 2 to 4 weeks, so you will need to keep her away from entire males during that time if she is not yet spayed. If you are still choosing a puppy, our guide to choosing a male or female dog covers what living with seasons is really like.

When to neuter a male dog

Castration is the less clear-cut decision. The BVA and BSAVA say it should be considered case by case, based on breed and lifestyle, and that "medical or surgical castration should not be carried out before physical maturity for the breed". Things your vet may weigh up include:

• your dog's age, breed and size
• why you want to neuter him (preventing breeding, health or behaviour)
• your lifestyle and his, including whether there is an entire female in the household
• his overall life expectancy and disease risk

Castration prevents testicular cancer and reduces the risk of prostate problems later in life. Compared with entire male dogs, castrated male dogs may also mount, scent mark and roam to find females less. For some males, a vet may suggest a temporary hormone implant, for example to cover a period when he must be kept from an entire female until surgery is appropriate, though it is not right for every dog.

How size and breed change the timing

Size is one of the biggest factors in when to neuter a dog, because large breed dogs take longer to grow.

Some breeds carry specific risks. The Royal Kennel Club lists Boxers, Dalmatians, Dobermanns and Weimaraners among breeds at higher risk of urinary incontinence after spaying, and says heavier dogs are also more at risk. Some research also links neutering to joint or back problems and the risk of certain cancers in particular breeds. Ask your vet whether anything is known about your breed, which you can also look up in our dog breeds guide.

Benefits of neutering and the possible risks

Neutering is not a trivial procedure, but the BVA says its benefits outweigh the welfare implications in many cases. These are the trade-offs to weigh when deciding whether neutering is right for your dog.

The incontinence risk is also linked to age: the Royal Kennel Club says dogs spayed before 6 months are twice as likely to develop it as those spayed between 6 and 12 months. Weight gain can be managed: the RSPCA says neutering "shouldn't mean weight gain" if you talk to your vet about diet.

Reasons for neutering: unwanted litters and dog theft

The BVA says neutering is the best way to prevent unwanted pregnancies, and BSAVA links it to keeping rescue centres from being overwhelmed with unwanted or neglected puppies. The RSPCA adds that unplanned litters can bring expensive vet bills, and that neutering lowers the risk of a dog being stolen for breeding.

Will neutering change my dog's behaviour?

Less than many people expect. For confident, well-socialised dogs, PDSA says neutering is unlikely to change their personality, but "if they are under-confident, fearful, or have behavioural problems, neutering could make them worse". The BVA notes evidence that castration can make fear-based aggression worse and does not reliably prevent aggression. Blue Cross says there is no real evidence that neutering calms young dogs.

If behaviour is your main reason for neutering, the BVA advises getting a behaviourist assessment first. Many of the things owners hope neutering will fix, such as pulling, jumping up and selective hearing, are normal teenage behaviour, which our guide to adolescent dogs explains.

Recovery after the neutering procedure

Most dogs go home the same day as the operation and recover there. Your dog may be sleepy for a few hours, and the anaesthetic can take up to a day to wear off. Follow your vet's discharge instructions exactly; this checklist covers the basics.

• Rest for 7 to 10 days. PDSA says rest for 7-10 days helps prevent complications with the wound and internal stitches; your dog may need lead walks only, a crate or one quiet room.
• No running or jumping. Keeping your dog calm helps the wound heal and prevents complications.
• Stop licking. Use a buster collar (cone), medical shirt or body suit; ask your vet first if you would prefer a soft option.
• Check the wound daily. Licking or damage can lead to infection or the wound opening.
• Go to every check-up. Dogs usually have post-op checks 2-3 days and 7-10 days after surgery.
• Stitches. Dissolvable stitches do not need removing; non-dissolvable stitches tend to be removed 7-14 days after the operation.
• Give only what your vet prescribes. Your dog will be given pain relief, and any medication sent home should be given as directed.
• Review their food. Once recovered, ask your vet about portion sizes or a food for neutered dogs.

Keeping up routine care around the operation helps too, so make sure worming your puppy and their flea treatment are up to date before the day, as your vet may ask.

How much does it cost to neuter a dog in the UK?

The Royal Kennel Club says neutering usually costs between £100 and £400, depending on your dog's breed, size and sex. Blue Cross explains why prices vary: spaying usually costs more than castration, castration can cost more if a testicle is retained, and larger dogs cost more because they need more anaesthetic and the surgery often takes longer. Pet insurance typically does not cover neutering, as it is treated as a routine cost of owning a dog.

Ask your own veterinary practice for a quote. If cost is a worry, PDSA suggests speaking to your vet practice and local dog warden to find out if any charity help is available.

When to call your vet

Call your vet straight away, or the out-of-hours service if your practice is closed, if after neutering your dog:

• has a wound that is bleeding, gaping, swollen, hot or leaking
• is still very drowsy, wobbly or unwilling to stand the next day
• refuses food for more than a day, or is vomiting
• seems in pain, is panting heavily or keeps crying
• has licked or chewed at the stitches
• (for males) has swelling or redness of the scrotum after surgery

For an unspayed female, pyometra often appears a few weeks after a season: signs include going off her food, lethargy or being very thirsty, and Blue Cross says to contact your vet immediately if you suspect it. If anything else worries you, ring your vet.

Frequently asked questions

Can I neuter my puppy at 6 months?

Some practices still do, and PDSA says most dogs can be neutered at around 6 months. The latest BVA and BSAVA guidance prefers waiting until a dog is mature, as neutering before 6 months is linked to higher orthopaedic risk.

Should I let my dog have one season before spaying?

It depends on your vet's view and your dog. Some vets spay before the first season to cut the risk of mammary cancer and pyometra, while others wait so hormones can finish maturing her.

Is it too late to neuter an older dog?

Not necessarily. The BVA says spaying older females after breeding still reduces the risk of pyometra and certain tumours. Your vet will check your dog is fit for an anaesthetic first.

Does neutering calm a dog down?

There is little evidence it does. It may reduce roaming and marking in males, but it can make fearful dogs worse.

Should I neuter my dog if I might breed from her later?

No. Neutering is permanent, so it is not suitable if you plan to breed. Talk to your vet about managing seasons until you decide.

Can I walk my dog after neutering?

Only gently, on a lead, until your vet says otherwise. PDSA advises 7-10 days of rest, then reintroducing exercise slowly once your dog has recovered.

Can a dog be spayed while in heat?

Many vets avoid it, and PDSA advises waiting approximately 3 months after a season before spaying.

Can I get my dog neutered for free in the UK?

Sometimes help is available. PDSA suggests asking your vet practice and local dog warden whether any charity help exists in your area.