When should I spay or neuter my dog?
Updated By PetymFacts checked against official sources on
Quick answer
Many dogs can be neutered from about 4 to 6 months, and PDSA says a female can be spayed before her first season. Larger dogs are different: UC Davis research found higher joint disorder rates in heavier dogs neutered before a year, so vets often suggest waiting until 12 months or later. Your vet decides for your dog.
The right age depends on size, breed, sex and your home, so ask at the puppy vaccine visits rather than waiting. For an indie of 20 kg or more, the same research suggests waiting until at least 12 months. If your female has had a season, PDSA advises waiting about three months before spaying.
What age does the research suggest, by size?
From Hart and others (2020), who studied mixed-breed dogs by expected adult weight using one US veterinary hospital's records.
| What the study found | What it suggested | |
|---|---|---|
| Under 20 kg Frontiers in Veterinary Sciencestudy | No increased risk of joint disorders with neutering at any age, and no clear rise in cancers | Owner and vet can choose the age |
| 20 to 29 kg Frontiers in Veterinary Sciencestudy | Higher joint disorder rates when neutered before 12 months | Wait until at least 12 months, both sexes |
| 30 to 39 kg Frontiers in Veterinary Sciencestudy | Joint disorders rose sharply in dogs neutered before a year | Wait until after a year |
| 40 kg and over Frontiers in Veterinary Sciencestudy | Males neutered before 6 months had about three times the joint disorder rate | Males around 2 years; females around 1 year |
A retrospective study from one hospital in California, with missing neutering ages in many records. Use it to start a conversation with your vet, not to set a date.
Does the age differ by breed?
Some breeds common in India, from the same team's 2020 study of 35 breeds. These are the authors' suggestions, not rules. In most breeds, they say, the owner can choose the age without raising these risks, and one rule cannot fit all dogs.
- Labrador Retriever
- Males: after 6 months. Females: after 1 year. Frontiers in Veterinary Sciencestudy
- Golden Retriever
- Males: after 1 year. Females: leave intact, or spay at about 1 year and watch for cancers. Frontiers in Veterinary Sciencestudy
- German Shepherd
- Males: after 2 years. Females: after 2 years. Frontiers in Veterinary Sciencestudy
- Rottweiler
- Males: after 1 year. Females: after 6 months. Frontiers in Veterinary Sciencestudy
- Boxer
- Males: after 2 years. Females: after 2 years. Frontiers in Veterinary Sciencestudy
- Beagle
- Males: after 1 year. Females: owner's choice. Frontiers in Veterinary Sciencestudy
- Shih Tzu
- Males: owner's choice. Females: at 2 years, or just before 6 months. Frontiers in Veterinary Sciencestudy
- Pomeranian, Dachshund
- Males: owner's choice. Females: owner's choice. Frontiers in Veterinary Sciencestudy
Why does the timing matter?
Because the benefits and the risks both change with age, and with size.
Neutering has clear benefits. PDSA says spaying prevents womb infection (pyometra), seasons, unwanted pregnancy and false pregnancy, and castration prevents testicular cancer and reduces prostate problems and the urge to roam. PDSA also says there is no evidence that having a litter first does a female dog any good.
The concern with early neutering is mainly joints, and mainly in bigger dogs. PDSA notes evidence that neutering large and giant breeds at 4 to 6 months can lead to joint problems later. Hart's 35-breed study found joint disorder risk was generally linked to body size: small breeds showed no increased joint risk, while some larger breeds did when neutered early.
The evidence on cancers is mixed. In the 35-breed study, cancer risk rose with neutering in only a few breeds; among small breeds, only the Boston Terrier and the Shih Tzu. For female Golden Retrievers the authors advise leaving them intact or spaying at about a year and watching for cancers. The authors also note that the evidence linking spaying to a lower risk of mammary cancer is weak, which matters because that link is often given as the main reason to spay early.
What do owners often get wrong about neutering age?
You may have read
A female should have one litter or one heat first.
Myth
What the sources say
PDSA says it is safe to spay before the first season and that there is no evidence a litter benefits a female dog. PDSA
You may have read
Every dog should be neutered at six months.
Myth
What the sources say
Hart and others found the safest age varies with size and breed, and suggested waiting a year or more for many heavier dogs. Frontiers in Veterinary Sciencestudy
You may have read
Earlier is always safer.
Myth
What the sources say
PDSA notes evidence that neutering large and giant breeds at 4 to 6 months can lead to joint problems later in life. PDSA
You may have read
Neutering will fix aggression.
Myth
What the sources say
PDSA says neutering can help some behaviours but may make nervousness worse, and in some cases can make aggression worse. PDSA
What should I ask my vet?
Take these to the puppy vaccine visits, so the decision is planned rather than rushed.
If Your dog will weigh under about 20 kg as an adult
Ask whether neutering from about 4 to 6 months suits your dog, or whether to spay a female before her first season. PDSA
If Your dog will weigh 20 kg or more, as many indies do
Ask whether to wait until at least 12 months, and longer for very large males. Frontiers in Veterinary Sciencestudy
If Your female has just had a season
PDSA advises waiting about three months after a season before spaying. Keep her away from entire males meanwhile. PDSA
If Your breed is in the 35-breed study
Ask your vet to look at that breed's findings with you, then decide together. Frontiers in Veterinary Sciencestudy
If You cannot keep an intact dog from mating, or from roaming
Tell your vet. Preventing unwanted litters is part of the decision, and the owner of a pet dog is responsible for its sterilisation under the ABC Rules, 2023. Ministry of Fisheries, Animal Husbandry and Dairying (Gazette of India copy on AWBI's site)
What about community dogs and adopted street dogs?
Street dogs are sterilised by the local body under the Animal Birth Control Rules, 2023 (G.S.R. 193(E)). Rule 11(9) says street dogs under six months are not captured for sterilisation, and mothers with puppies are not captured until the litter is two months old. Rule 11(16) requires a V-shaped notch on the right ear to mark a dog as sterilised and immunised.
Once you adopt a dog and keep it at home, rule 8(1) makes you, as its owner, responsible for its deworming, immunisation and sterilisation. If an adopted indie has no ear notch, ask your vet whether it is sterilised and, if not, when to do it. Petym's answer on adopting an indie dog and the glossary entry on spaying and neutering go further.
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Questions owners ask
What is the right age to spay a female dog?
- There is no single age. PDSA says most dogs can be neutered from 4 to 6 months and a female can be spayed before her first season, but larger dogs may do better later: Hart and others suggested about a year or more for many heavier dogs. Your vet decides, based on size and breed.
Should I spay my dog before or after her first heat?
- Either can be right. PDSA says spaying before the first season is safe, and that after a season you should wait about three months. For large breeds, research suggests waiting until after a year may lower joint risks, which often means after a first season. Ask your vet.
When should I neuter a male dog?
- For small dogs, PDSA's general window of 4 to 6 months often applies. For larger dogs, research from UC Davis suggests waiting: at least 12 months for dogs of 20 to 29 kg, and around 2 years for males of 40 kg or more. Breed matters too, so ask your vet.
When should I neuter an indie dog?
- Many indies weigh 15 to 30 kg as adults. Hart and others found no joint risk with neutering at any age in mixed-breed dogs under 20 kg, but suggested waiting until at least 12 months for dogs of 20 to 29 kg. Your vet can estimate your indie's adult weight and advise.
Is it too late to neuter an older dog?
- Not usually. Dogs can be neutered as adults, and the research on timing is mostly about the risks of neutering too early. An older dog may need checks before an anaesthetic, so ask your vet whether neutering suits your dog's age and health.
Keep reading
- Spaying and neuteringWhat the operations are, and recovery at home.
- Pyometra
- Puppies
- Dog vaccination schedule
- Indian pariah dog
Free tools for this
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Sources
Each source was opened and read on the date shown. How Petym checks its sources
- PDSA: Dog neutering: a guide to castration and spaying (opens in a new tab)
- Ministry of Fisheries, Animal Husbandry and Dairying (Gazette of India copy on AWBI's site): Animal Birth Control Rules, 2023: G.S.R. 193(E), 10 March 2023 (opens in a new tab)
- INDog Project (independent; not a kennel club): Breed standard of the Indian native dog (opens in a new tab)
- Frontiers in Veterinary Science: Assisting decision-making on age of neutering for 35 breeds of dogs: associated joint disorders, cancers, and urinary incontinence, Hart and others, 2020 (opens in a new tab)
- Frontiers in Veterinary Science: Assisting decision-making on age of neutering for mixed breed dogs of five weight categories: associated joint disorders and cancers, Hart and others, 2020 (opens in a new tab)