What month of the year do cats have kittens, and can cats have kittens in the winter months? Find out more about when cats breed in the UK

With spring in the air and summer on its way, you may have heard about ‘kitten season’ and started to see more kittens available to adopt and buy.

Although kittens can be born at any time of year, the majority will arrive during the period between March and September in the UK, which is why we call this kitten season.

Cats are more likely to breed during these months because the hormonal changes required for an unneutered female cat to start her reproductive cycle (known as ‘coming into heat’) are dependent on daylight.

When the days start to get longer, her hormones will change and stimulate the ovary to produce an egg.

In the northern hemisphere, this will start from January or February, and can continue as late as October or November. The majority of cats will be at peak fertility when the daylength is over 12 hours. For cats who live close to the equator, this seasonality isn’t as noticeable.

Unneutered female cats will come into heat every two to three weeks during these spring and summer months until they have successfully mated with an unneutered male cat. They can come into heat several times a year and during this time they will become very restless and noisy as they call for a mate.

The average length of pregnancy for a cat is around nine weeks, so cats who are pregnant toward the beginning of this period will have their kittens in early spring, around March time.

After giving birth, female cats can get pregnant again as soon as two weeks later and could end up having up to 18 kittens a year!

At Cats Protection, we notice the effects of ‘kitten season’ every year as the number of pregnant cats and unwanted kittens arriving in our care starts to increase steadily from March to May, peaks in June to September and then starts to decrease in October and November. In July 2022, 50% of the cats in our care were kittens.

This puts a lot of pressure on our centres and branches as pregnant cats and kittens require a lot of care. It also means that the older cats waiting for new homes often get overlooked in favour of the cute kittens, meaning they stay with us for longer.

To help ease the burden of ‘kitten season’, it’s important to get your cat neutered before they are able to breed, which is when they are around four months old. Not only will this prevent unneutered kittens from being born, but it will also have many other benefits for you and your cat.

Find out the benefits of neutering and how to get your cat neutered.