| Puppy series start age | 6–8 weeks (American Animal Hospital Association (AAHA) Canine Vaccination Guidelines) |
| Kitten series start age | 6–8 weeks (American Association of Feline Practitioners (AAFP) Vaccination Guidelines) |
| Puppy/kitten booster interval | Every 3–4 weeks until ~16 weeks old (AAHA and AAFP guidelines) |
| Rabies vaccine (first dose) | Typically 12–16 weeks; varies by local law (Varies by state and municipality) |
| Adult core booster frequency | 1-year booster, then every 1–3 years (AAHA Canine Vaccination Guidelines) |
| Bordetella booster frequency | Every 6–12 months for at-risk dogs (AAHA non-core vaccine recommendations) |
Core vs. Non-Core Vaccines: Understanding the Difference
Veterinary guidelines divide pet vaccines into two broad categories: core and non-core. Knowing which is which helps you have more informed conversations with your vet.
Core vaccine
A vaccine recommended for all pets of a given species, regardless of lifestyle, because the disease it prevents is widespread, serious, or poses a public health risk.
Non-core vaccine
A vaccine recommended selectively based on a pet's individual risk factors, such as geographic location, outdoor exposure, or contact with other animals.
Maternal antibodies
Protective proteins passed from a mother to her offspring that can temporarily block vaccines from generating full immunity in very young animals.
Booster
A follow-up dose of a vaccine given after the initial series to maintain or renew a pet's immunity over time.
FVRCP
A combination vaccine for cats covering feline viral rhinotracheitis (herpesvirus-1), calicivirus, and panleukopenia — considered a core vaccine for all cats.
Core vaccines are recommended for virtually every dog or cat, regardless of lifestyle. They protect against diseases that are widespread, severe, or transmissible to humans. For dogs, core vaccines generally include distemper, parvovirus, adenovirus, and rabies. For cats, core vaccines typically include feline panleukopenia (distemper), feline herpesvirus-1, feline calicivirus (often combined as FVRCP), and rabies.
Non-core vaccines are recommended based on a pet's individual risk factors — where they live, how much time they spend outdoors, and whether they interact with other animals. Examples include the Bordetella (kennel cough) vaccine for dogs that visit boarding facilities, or the feline leukemia virus (FeLV) vaccine for cats that go outside. Your veterinarian is the right person to assess which non-core vaccines make sense for your specific pet.
This article provides general educational information only and is not a substitute for veterinary advice. Always consult your veterinarian for guidance tailored to your pet.
Puppy and Kitten Vaccine Series: The Early Weeks
Young animals receive a series of vaccines — not just a single shot — because maternal antibodies (passed from mother to offspring) can interfere with vaccine effectiveness. Spacing out doses allows immunity to build reliably as those maternal antibodies wane.
| Puppy series start age | 6–8 weeks (American Animal Hospital Association (AAHA) Canine Vaccination Guidelines) |
| Kitten series start age | 6–8 weeks (American Association of Feline Practitioners (AAFP) Vaccination Guidelines) |
| Puppy/kitten booster interval | Every 3–4 weeks until ~16 weeks old (AAHA and AAFP guidelines) |
| Rabies vaccine (first dose) | Typically 12–16 weeks; varies by local law (Varies by state and municipality) |
| Adult core booster frequency | 1-year booster, then every 1–3 years (AAHA Canine Vaccination Guidelines) |
| Bordetella booster frequency | Every 6–12 months for at-risk dogs (AAHA non-core vaccine recommendations) |
For puppies, the typical schedule begins around 6–8 weeks of age and continues with boosters every 3–4 weeks until the puppy is about 16 weeks old. The rabies vaccine is generally given once between 12 and 16 weeks, depending on local regulations. A booster follows one year later.
For kittens, the FVRCP series commonly starts at 6–8 weeks, with boosters at 3–4 week intervals until about 16 weeks of age. Rabies vaccination timing follows local law, usually beginning around 12–16 weeks. Kittens at risk for FeLV may receive that vaccine starting at 8 weeks with a booster 3–4 weeks later.
This early period is also covered in depth in our guide to your pet's first year, which walks through vet visits, feeding, and other milestones new owners should prepare for.
Adult Booster Schedules and Ongoing Protection
Once the initial series is complete, most core vaccines shift to a booster given at one year, then — depending on the specific vaccine and your veterinarian's recommendation — every one to three years thereafter. Rabies booster intervals are often set by state or local law, so your vet will know the requirements for your area.
Titer Testing: An Option Worth Asking About
Some veterinarians offer titer tests — blood tests that measure an animal's existing antibody levels — as a way to help determine whether a booster is currently needed for certain core vaccines. Titer testing is not appropriate for all vaccines (rabies, for example, is usually governed by law), and its use varies by practice. If you have questions about your pet's booster timing, ask your veterinarian whether titer testing might be relevant for your situation.
Non-core vaccines like Bordetella may require more frequent boosters (sometimes annually or even every six months for high-exposure dogs) because the protection they confer tends to be shorter-lived. Your vet will factor in your pet's lifestyle when recommending a schedule.
As pets age, vaccination needs can shift. Senior animals may have different immune responses and health considerations that influence how a vet approaches boosters. Our article on senior pet veterinary care explains what typically changes as your pet enters its later years.
Vaccine costs are a real consideration for many families. If you're weighing how to budget for ongoing preventive care, it's worth understanding how pet insurance works and what it typically covers, since some plans include or offset wellness care. For a broader view of lifelong pet health, see our end-to-end pet care overview.
This article is for general informational purposes only and does not constitute veterinary advice. Consult a licensed veterinarian for recommendations specific to your pet's health, age, and lifestyle.