Do indoor cats need vaccines? Yes. According to the Cornell Feline Health Center, the American Association of Feline Practitioners (AAFP) recommends that even cats who never set a paw outside get the core vaccines: panleukopenia, feline herpesvirus, calicivirus and rabies. In Ontario, rabies vaccination is also the law for every cat three months or older, indoor or not.
It's a fair question, though. If your cat's whole world is a one-bedroom on the fourth floor, what could she possibly catch? More than you'd think. New cats bring germs home, bats get inside, and cats slip out doors. Here's what each core vaccine protects against, what's optional, and how your vet decides what your cat actually needs.
Do indoor cats need vaccines? The short answer
Yes, for the core vaccines, the ones every cat should have. Cornell lists these as the AAFP panel's recommendation for household cats kept indoors at all times:
| Vaccine | What the disease does |
|---|---|
| Panleukopenia (feline distemper) | A highly contagious, potentially lethal virus causing fever, vomiting, diarrhea and loss of appetite; kittens are especially at risk |
| Feline herpesvirus (rhinotracheitis) | Upper respiratory infection: sneezing, eye and nose discharge, conjunctivitis |
| Calicivirus | A highly contagious, widespread virus and a major cause of upper respiratory infection |
| Rabies | A fatal disease for people and animals, spread through the saliva of a rabid animal by a bite or scratch |
Feline leukemia virus (FeLV) is its own case. Cornell says the FeLV vaccine is core for all cats under one year, and non-core for cats a year and older with no potential exposure to infected cats or cats of unknown status.
Indoor-only cats still need core vaccines. Staying inside lowers the risk of disease; it doesn't make it zero.
Rabies: required by law in Ontario
In Ontario, an indoor cat still needs a rabies shot by law. Regulation 567 says every owner or person caring for a cat, dog or ferret three months of age or older must make sure it's immunized against rabies, and reimmunized by the date on its certificate. There's no indoor exception. A vet can only issue a medical exemption when a condition makes the vaccine unsafe, and then the cat has to be kept from exposure. Our post on the rabies vaccine Ontario law has the details.
And the risk behind the law is real. The Cornell Feline Health Center notes that bats, which have a high rate of rabies, commonly find their way indoors through small cracks into houses and apartments. Picture a bat loose in the living room at 2 a.m. Now picture your cat. Many cats will chase it.
How indoor cats get exposed
Indoor cats get exposed in small, easy-to-miss ways, which is why vets now ask more detailed questions. In 2020, the AAFP and the American Animal Hospital Association released feline vaccination guidelines that move away from a simple indoor or outdoor label. The AAFP's president at the time said vets can no longer just ask whether a cat is "indoors" or "outdoors," because owners may not count brief time outside.
So expect questions like these. Does your cat sit out on a balcony, a patio or a catio, or by an open window? Ever visit a friend's place, a groomer or a boarding cattery? Go for walks on a leash? And what about the other cats at home: does anyone go outside, or is anyone new?
Cornell adds that an indoor-only cat can sneak out through an open window or door, or escape when carried outside for a vet trip. A carrier prevents most of those escapes. It also notes that no vaccine is 100 percent effective, so even a vaccinated cat should have limited contact with sick cats.
Kittens and cats with an unknown history
Kittens get a series of vaccines over a 12 to 16 week period, starting between 6 and 8 weeks of age, Cornell says. Earlier shots don't work well because antibodies from the mother's milk get in the way.
Adopted an adult cat with no paperwork? Cornell says to treat a cat with an unknown vaccine history as unvaccinated and give the full kitten series, and an overdue adult cat gets boosters no matter how long it's been. Just tell your vet what you know, and they'll set a plan. Our dog and cat vaccine schedule for Canada gives the overall shape.
What about vaccine risks?
Cornell describes the risks as rather minimal compared with the benefits: mainly allergic reactions in the short term and, rarely, injection site sarcomas in the long term. That's one reason the AAFP and AAHA guidelines tailor non-core vaccines to each cat instead of giving everything to everyone.
Tell your vet about any past reaction, and keep an eye on your cat after a shot. If anything seems wrong, call your vet right away. Same goes for a lump at an injection site that doesn't go away.
Non-core vaccines: your cat's lifestyle decides
Beyond the core list, it depends on your cat. Cornell says the decision comes from a careful look at lifestyle, age, health, contact with other cats, vaccine history and medications. A strictly indoor adult cat who lives alone may need nothing beyond the core vaccines, while a cat who boards or shares a home with outdoor cats may need more. Bring it up at the yearly visit.
Then keep the plan somewhere you'll see it. In the free PetGrid app you can record each vaccine and its next due date, get reminders before boosters are due, and share a vaccine card when your cat goes to a sitter or cattery.
Questions people ask
Do indoor cats need a rabies vaccine?
Yes. The AAFP lists rabies as a core vaccine for indoor cats, and in Ontario the law requires every cat three months or older to be vaccinated. Bats can get into homes, and plenty of cats will chase them.
What shots does an indoor cat need?
The core vaccines: panleukopenia, feline herpesvirus, calicivirus and rabies. Kittens under one year should also get the FeLV vaccine; after that, your vet decides based on your cat's exposure to other cats.
How often do indoor cats need vaccines?
It depends on the vaccine and the product used, so follow your vet's schedule and the due date on your rabies certificate. Adult cats who are overdue should get boosters whenever the gap is noticed.
Can an indoor cat get sick from another cat's germs?
Yes, it can. Viruses can spread through new cats, other cats in the home, boarding, grooming, or time on a balcony or near an open window, which is why the AAFP asks about all of these.
My adopted indoor cat has no vaccine records. What now?
Cornell says a cat with an unknown history should be treated as unvaccinated and get the full kitten series. Ask your vet to set the schedule.
The short version
So, do indoor cats need vaccines? Yes for the core four, and in Ontario, rabies is the law. Living indoors changes which extras make sense, and your vet will fit those to your cat's real life, balcony, catio and roommates included.
The free PetGrid app keeps your cat's vaccines, due dates and certificates in one place, so the next booster doesn't sneak up on you.
Keep your pet's records, vaccines and visits in one safe place. The PetGrid app is free for pet owners, with or without a clinic.
Get the free PetGrid appSources
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