Vaccinations
A small injection. A few minutes at the vet. And a level of protection that can genuinely save your cat's life. Vaccinations are one of the simplest and most important things you can do for your cat — and yet vaccination rates in the UK have been quietly falling for years. Here's everything you need to know.
What do vaccinations actually do?
Vaccines work by introducing a harmless version of a virus or bacteria to your cat's immune system. The immune system responds by building defences — antibodies and disease-fighting cells — so that if your cat ever encounters the real thing, their body is ready to fight it off. A vaccinated cat who does encounter a disease will either avoid it altogether or experience a much milder version than an unvaccinated cat.
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Some viruses can cause severe illness and death, particularly in unvaccinated kittens — and some can be brought into the home on shoes, clothing or contaminated surfaces, meaning even indoor cats are not completely safe.
What does the vaccine protect against?
In the UK, cats are vaccinated against three core diseases as standard:
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Feline Enteritis (Feline Parvovirus / FPV)
A highly contagious parvovirus spread through direct contact and contaminated environments. Symptoms include lethargy, bloody diarrhoea, vomiting, fever and depression. The mortality rate is high, particularly in unvaccinated kittens. It can survive in the environment for a long time and is resistant to many common disinfectants. Vaccination has made this disease rare — but unvaccinated cats remain at serious risk.
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Cat Flu (Feline Herpesvirus and Feline Calicivirus)
These two viruses are always vaccinated against together, as they are the main causes of upper respiratory tract infections in cats. Symptoms include sneezing, eye discharge and mouth ulcers. Although vaccination doesn't always prevent infection entirely, it significantly reduces the severity of the disease if a vaccinated cat does become infected. Calicivirus can additionally cause tongue ulceration, joint swelling and painful mouth inflammation.
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Feline Leukaemia Virus (FeLV) FeLV
This is contagious through bodily secretions and can be passed between cats through close contact, mutual grooming or biting. FeLV is ultimately fatal. Vaccination is particularly recommended for cats who go outside, or indoor cats who live with other cats who do go outside.
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A note on Rabies
In many countries — including the USA, Australia and much of Europe — rabies vaccination is either legally required or strongly recommended, as rabies is present in the wild animal population. If you're reading this from outside the UK, check with your vet about the requirements and recommendations in your country.
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In the UK, rabies has been eradicated and vaccination is not routinely required. The exception is if you are travelling internationally with your cat under the Pet Travel Scheme — in which case rabies vaccination becomes a legal requirement before your cat can travel and return to the UK.
The vaccination schedule
Kittens need a course of two vaccinations, starting from eight weeks of age, with the second injection given three to four weeks later. All kittens should stay indoors and away from other cats for seven days after the second injection to make sure they are fully protected.
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After the initial kitten course, the full vaccine is repeated one year later. Annual boosters are then required to maintain immunity against cat flu, while the feline enteritis and leukaemia vaccine is typically repeated every three years — though your vet will advise on the right schedule for your individual cat.
Do indoor cats need vaccinating?
Yes — and this is one of the most common misconceptions. Both indoor and outdoor cats are at risk because viruses like feline calicivirus can be carried into the home on shoes and clothing. An indoor cat can also escape unexpectedly, or come into contact with other cats at the vet or cattery. The protection vaccinations provide is simply too important to skip.
What about catteries?
Cats visiting a cattery are at particular risk because they share air space with other cats. For this reason, almost all boarding facilities require cats to have received a vaccination booster within 12 months prior to admission. If your cat's boosters have lapsed, get them updated before booking any cattery stay.
What happens if you miss a booster?
If your cat misses a booster, your vet may recommend restarting the vaccination course. Missing boosters can mean paying for a full primary course again rather than a single booster — so staying on schedule is both better for your cat and kinder to your wallet. Most vet practices will send reminder texts or emails, but it's always worth making a note yourself too.
Are there any side effects?
Cat vaccinations are very safe. Most cats tolerate vaccines well, but mild side effects can occur, including a slight fever, reduced appetite and swelling at the injection site. These typically pass within a day or two. If you notice anything more concerning — persistent lethargy, significant swelling or any allergic reaction — contact your vet straight away.
The cost
The average cost for an initial kitten vaccination course in the UK is between £40 and £100. Annual booster vaccinations typically cost between £40 and £60, though prices can be higher depending on location and practice.
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Many vet practices offer preventative care plans — often called Pet Health Club or similar — which spread the cost across monthly payments and can work out cheaper than paying per visit. Charities such as the PDSA, RSPCA and Blue Cross can help with the cost of vaccinations for owners on a low income or certain benefits.
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Prices correct at time of publication, June 2026. We recommend checking directly with your vet for current costs.
I've heard concerns about vaccinations — what should I know?
You're not alone. Concerns about vaccinations — for both people and pets — are increasingly common, and asking questions is always the right thing to do. Here's an honest look at the most frequently raised worries, specifically for cats:
"My cat had a reaction last time"
Mild reactions — slight lethargy, reduced appetite, a little soreness at the injection site — are normal and usually pass within 24 to 48 hours. Serious reactions are rare but do happen. If your cat has had a significant reaction previously, tell your vet before the next vaccination. They can monitor your cat more closely afterwards, adjust the vaccine type, or discuss whether the benefits still outweigh the risks for your individual cat. This is a conversation worth having — not a reason to stop vaccinating altogether without guidance.
"I'm worried about over-vaccination"
This is a legitimate concern and one that vets take seriously. Not every vaccine needs to be given every year — as we covered above, some protection lasts up to three years. If you're concerned about unnecessary boosters, ask your vet about titre testing. This is a simple blood test that measures whether your cat still has adequate levels of immunity from a previous vaccine. If immunity is still strong, a booster may not be needed yet. Titre testing is a recognised, vet-approved option that lets you make an informed decision rather than vaccinating automatically.
"I've read that vaccines can cause illness"
The diseases that vaccines protect against — feline enteritis, cat flu and FeLV — are significantly more dangerous than the vaccines themselves. Feline enteritis, for example, has a high mortality rate in unvaccinated kittens. The vaccine carries a very small risk of mild side effects. The disease carries a very real risk of serious illness or death. That comparison matters.
"My cat is indoor-only — surely they don't need it?"
As covered above — sadly, yes they do. Viruses can enter your home on clothing, shoes and hands. Your cat may escape unexpectedly. They may need emergency vet care alongside other cats. The risk is lower for indoor cats, but it is not zero.
The bottom line
Vaccination decisions should always be made with your vet, based on your cat's individual health, lifestyle and history. If you have concerns, voice them — a good vet will always take the time to talk them through with you. What matters most is that your cat gets the protection they need, in the way that's right for them.