A guide to kitten vaccinations

Reviewed by Dr Siân Burwood MA VetMB MRCVS

Welcoming a new kitten into your home is exciting – and vaccinations are one of the most important steps in keeping them healthy. If you’re new to kitten care, it’s completely normal to have questions about which injections are needed, when they should be given, and when it’s finally safe for your kitten to explore the outside world.

We explain why vaccinating your kitten matters, what the UK vaccination schedule looks like, and how to give your curious cat the best possible start in life.

• Why vaccinating your kitten is essential
• Which vaccinations do kittens need in the UK?
• How many injections will my kitten need?
• How much do kitten vaccinations cost?
• When is it safe for kittens to go outside?
• Common questions about kitten vaccinations

Why vaccinating your kitten is essential

Vaccinating your kitten is one of the most effective ways to protect them from some serious and potentially life-threatening viral diseases. Young kittens have developing immune systems, which makes them particularly vulnerable to these infections, some of which can kill, and some of which cause lifelong disease.

Vaccinations don’t just protect your own kitten – they also help reduce the spread of disease to other cats. Once your kitten has completed their initial vaccination course, vets recommend continuing with booster injections once a year throughout adulthood and into later life to keep this protection up to date. If your cat misses a booster, they’ll need to start the course again to ensure they have enough protection

Vaccination is so important that any insurers will not cover illnesses that could have been prevented by routine vaccinations. It’s worth checking your pet insurance policy carefully.

Can unvaccinated kittens mix with vaccinated cats?

In some cases, an unvaccinated kitten may be around a healthy, fully vaccinated adult cat. However, most vets advise caution. Until your kitten has completed their primary vaccinations and allowed time for immunity to develop, it’s usually best to keep them indoors and away from unfamiliar cats.

Because kittens are still growing and their immune system is not fully developed, they’re at a higher risk of becoming unwell. Contact with unvaccinated kittens or outdoor cats should be avoided until your vet confirms it’s safe.

Which vaccinations do kittens need in the UK?

In the UK, kittens are routinely vaccinated against cat flu and feline parvovirus. If your cat is likely to go outdoors or come into contact with other cats, vaccination against feline leukaemia virus is also strongly recommended.

If you live outside the UK, vaccination requirements may differ, so always check local guidelines.

Cat flu (feline influenza)

Cat flu is a highly contagious respiratory illness that can be particularly severe in kittens and elderly cats. It’s not actually caused by a flu virus, but by a combination of feline herpes virus and calicivirus.

• It spreads through saliva, nasal discharge and objects contaminated by these fluids, like bowls or bedding.
• Symptoms may include sneezing, runny nose, fever, coughing and watery eyes.
• Some kittens may also develop mouth ulcers, eye ulcers, lethargy and reduced appetite.
• Cats can become long-term carriers and experience flare-ups throughout their lives.
• Calicivirus is also associated with the ‘gingivitis stomatitis complex’, a nasty mouth condition that needs early and repeated dental care to treat.
• Vaccination won’t always prevent infection entirely, but can reduce severity and frequency of symptoms.

Feline parvovirus (FPV, feline enteritis or panleukopenia)

Feline enteritis or panleucopenia is a serious and often fatal disease, similar to parvovirus in dogs. It attacks the immune system and the lining of the intestines, and in some cases affects the heart.

• The virus spreads through contact with infected cats, their faeces or contaminated environments.
• Pregnant cats can pass the virus to their unborn kittens, sometimes resulting in cerebellar hypoplasia, a birth defect where the movement centre of the brain doesn’t fully develop.
• Symptoms include fever, lethargy, vomiting, diarrhoea and loss of appetite.
• Kittens infected before birth may show coordination, movement or vision problems.
• It requires aggressive treatment and is often fatal.

Feline leukaemia virus (FeLV)

Feline leukaemia virus is another serious condition that weakens the immune system and increases susceptibility to other infections.

• The virus is spread through bodily fluids including saliva, urine and faeces.
• Signs may include weight loss, lethargy, fever, vomiting, diarrhoea, anaemia and poor appetite.
• It can also lead to cancers such as leukaemia and lymphoma, both of which might not develop for several years.
• There is no cure for FeLV, making vaccination a key preventive measure.

Additional vaccinations

If you plan to travel abroad with your cat, a rabies vaccination is legally required at least 21 days before travel. Rabies is a fatal disease transmitted through saliva and can cause neurological symptoms such as seizures, paralysis and behavioural changes. It can also be transmitted to humans. It’s not currently present in the UK, and all pet travel requirements are about keeping it out. Think very carefully about whether your cat needs to travel outside the UK and consult your vet in plenty of time if travel is essential.

Some kittens may also be vaccinated against feline chlamydia, a bacterial infection spread through close contact with infected cats. Symptoms are similar to cat flu and include conjunctivitis, sneezing, fever and eye discharge.

How many injections will my kitten need?

Kittens require a primary vaccination course to build proper immunity. This usually consists of two injections, though in some situations a third dose may be advised depending on risk factors. The primary vaccination course technically also includes the first annual booster.

When should vaccinations start?

The first vaccination is typically given from around nine weeks of age. The second injection is usually administered two to four weeks later. Vaccinations can be given at any age however, so if your cat comes to you later than this age, you should still make sure you get to the vet ASAP.

How often are booster vaccinations needed?

After the initial course, cats need booster vaccinations every year to maintain protection. Some vaccines may only need boosting every few years, and your vet will advise you based on your cat’s lifestyle and health.

Guidelines for the UK advise vaccinating against cat flu and panleucopenia every year, and feline leukaemia virus every 3 years after the first annual booster.

How much do kitten vaccinations cost in the UK?

The cost of kitten vaccinations varies between veterinary practices, so it’s best to contact your local clinic for exact pricing. According to Catster, the primary vaccination course in the UK can cost anywhere between ​ ​£40-£100, while annual boosters are about £40-£60, though this can vary by location.

Many practices also offer healthcare plans, which allow you to spread the cost through monthly payments. These plans often include vaccinations, annual health checks and parasite treatments.

When is it safe for kittens to go outside?

It’s safe for kittens to go outside typically one week after the second vaccination of their primary vaccination course. Until then, they should remain indoors, even if they’re desperate to explore.

Vaccinations are just one part of this question, however. Your vet will advise you not to let your cat outside until they’re also microchipped and neutered. This can be done from 12-16 weeks of age depending on practice policy.

Animal welfare charities such as ​ ​Blue Cross recommend waiting until a kitten is around five months old before allowing outdoor access, as they’re then closer to full physical development and more able to cope with the challenges of the outside world.

It’s important to remember that microchipping is now compulsory in the UK. Having your kitten microchipped means they can be identified and reunited with you if they wander off. This must be done before they’re 20 weeks old. Many practices will do this while your cat is under anaesthetic for neutering, meaning they won’t feel it.

Can kittens go into the garden before vaccinations?

Because kittens are excellent climbers and escape artists, it’s usually safest to wait until they’re fully vaccinated before letting them into the garden. Even enclosed spaces can pose a risk if your kitten manages to get out.

Find out how to create a cat-friendly garden.

My kitten went outside before being vaccinated

If your kitten has been outdoors before completing their vaccinations, there’s a risk they could have been exposed to infection. Contact your vet for advice – they may recommend a health check or monitoring for symptoms.

My kitten missed their second vaccination

If your kitten is late for their second injection, book a vet appointment as soon as possible. Depending on how long it’s been, your vet may still be able to continue the course or may advise restarting it to ensure full protection.

‘Why bother with vaccines?’ A vet’s take

“Having worked in both the UK and countries where routine vaccination does not happen, I’ve seen firsthand what a difference vaccination can make and how many lives it saves. It’s truly heartbreaking to see a young kitten die from a preventable disease, or to see a family lose a beloved pet to a cancer that was avoidable.

“I always say that the healthiest cats see me once a year for vaccination and a check up. It’s a great opportunity to do a physical examination and look for early signs of disease that might not be so obvious when you live with them daily. Prevention is always better than cure.”

Dr Siân Burwood MA VetMB MRCVS

Common questions about kitten vaccinations

Are there side effects from kitten vaccinations?

Most kittens tolerate vaccinations very well. Mild side effects can occur and usually resolve within 24-48 hours. These may include tiredness, reduced appetite, sneezing or a slight fever. You can sometimes also feel a small pea-sized swelling at the site of the injection, which will usually resolve within a few weeks.

Serious reactions are extremely rare. If you’re worried about any symptoms following vaccination, contact your vet for reassurance.

Can I vaccinate my kitten at home?

Vaccinations should only be given by a qualified veterinary professional to ensure both that they’re administered safely and correctly, and that only safe licensed products are used. Home vaccinations are only carried out in specific circumstances and under veterinary guidance.

How else can I protect my kitten’s health?

During vaccination visits, your vet will often discuss other essential aspects of kitten care, including:

• Microchipping, which is a legal requirement in the UK – it must be done before cats reach 20 weeks
• Nutrition, including choosing a balanced diet and switching foods safely
• Parasite control. All kittens will have some worms from their mother, so regular worming while they’re developing is important. Depending on their lifestyle, they may also need treatment for fleas and mites. There are lots of different options so speak to your vet about the right one for you and your cat

We all want the best for our kittens. That’s why we offer lifetime kitten insurance, helping to protect their health now and in the years ahead.