Puppy Year One / Spay and neuter timing for puppies

Spay and neuter timing for puppies

Quick answerAAHA’s guidelines suggest neutering small breeds at about 6 months and waiting until growth stops for large breeds, and spaying small breeds before the first heat (5 to 6 months) while large breeds wait until growth stops. Your vet makes the call for your dog.

Your puppy’s first year, organizedCreate a profile, track weight and notes, set medication reminders and ask questions any hour of the day.Raise a happy puppy with every note in one place. Free to download. Try it free, no payment info needed, then decide after the trial.What is PawLine? An AI-powered pet health app whose answers draw on published veterinary research, including sources like PubMed. Ask health questions any hour, get emergency triage and first-aid steps, set medication reminders, keep a profile and daily notes for each pet and email them to your vet, and find nearby vets. Try it free for 30 days with no payment info needed; after the trial, continued access is an in-app purchase (weekly or yearly). Guidance only, not a diagnosis.

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Published Oct 19, 2026 · Updated Oct 19, 2026 · By the Editorial team. General education, not veterinary advice and not yet individually reviewed by a licensed veterinarian. About and sources

AAHA 2019 proposed ages

	Small breeds (under 45 lb adult)	Large breeds (45 lb or more adult)
Castration (male)	6 months	After growth stops, about 9 to 15 months
Spay (female)	Before first heat, about 5 to 6 months	After growth stops, about 5 to 15 months

Your puppy’s first year, organized

Create a profile, track weight and notes, set medication reminders and ask questions any hour of the day.

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Complete pet profilesBreed, age, weight, health conditions and photos for each pet, so advice fits that animal.
Instant health answersAsk about a symptom, diet or behavior question and get a research-backed answer, day or night.
Daily health notesWrite down symptoms and observations, then share the records with your vet by email.

Raise a happy puppy with every note in one place. Free to download. Try it free, no payment info needed, then decide after the trial.

What is PawLine? An AI-powered pet health app whose answers draw on published veterinary research, including sources like PubMed: instant health answers, emergency triage with first-aid steps, medication reminders, pet profiles and daily notes you can email to your vet, and nearby vet search. The 30-day free trial needs no payment info; after it, continued access is an in-app purchase, weekly or yearly (see the store listing). PawLine gives guidance and information, not a diagnosis. Always consult a licensed veterinarian for medical decisions.

Why there is a range

AAHA says to use clinical judgment and owner education to balance the benefit of earlier spay (less mammary tumor risk and no unwanted litters) against later timing (less risk of orthopedic disease, some cancers and urinary incontinence).

Raise a happy puppy with every note in one place. Get PawLine on the App Store · Get it on Google Play

Questions for your vet

What is my puppy’s projected adult weight?
What are the risks and benefits for this breed?
What do I do about heat cycles in the meantime?
What is aftercare, and what warning signs should I watch for?

Frequently asked questions

When should I spay or neuter my puppy?

AAHA’s 2019 guidelines give breed-size ranges. Small breeds about 5 to 6 months for spay and 6 months for neuter; large breeds after growth stops. Ask your vet.

Your puppy’s first year, organized

Create a profile, track weight and notes, set medication reminders and ask questions any hour of the day.

Download on theApp Store Get it onGoogle Play

Complete pet profilesBreed, age, weight, health conditions and photos for each pet, so advice fits that animal.
Instant health answersAsk about a symptom, diet or behavior question and get a research-backed answer, day or night.
Daily health notesWrite down symptoms and observations, then share the records with your vet by email.
Medication remindersSet medication schedules for every pet, get push notifications, and track dosing history.
Emergency triageHelps you judge whether your pet needs urgent veterinary care, with step-by-step first aid while you get to the vet.
Nearby vets and pet placesFind vet clinics, dog parks, groomers and pet shops, and save favorites.
Birthday remindersA reminder before each birthday with breed facts.
Many speciesDogs, cats, birds, rabbits, reptiles, small pets, and livestock such as horses, goats, sheep, cows and chickens.

Raise a happy puppy with every note in one place. Free to download. Try it free, no payment info needed, then decide after the trial.

Sources

AAHA 2019 Canine Life Stage Guidelines: proposed ages for sterilization https://www.aaha.org/resources/life-stage-canine-2019/spay-and-neuter-timing/

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