How often should you worm your cat?

Why ‘twice a year’ is too little for one cat and too much for another

Look up how often a cat needs worming and you get articles with a single number that applies to every cat. Yet this is exactly the question where the answer differs per animal: a cat that never leaves the flat runs a very different risk from one that brings in a mouse every week. Between those two sits a factor of four. This planner asks the questions the guidance asks and works out the schedule for your cat, including the date of the next treatment. If your cat is in the cat passport, it picks up the birth date and whether your cat goes outdoors automatically.

Common questions about worming

How often should I worm my cat?

It depends on your cat. A cat that lives strictly indoors can be treated or tested once or twice a year. A cat that goes outdoors should be dealt with at least four times a year, and a cat that regularly catches and eats mice or birds more often still. Kittens follow their own schedule: a first worming at three weeks, then every two weeks until two weeks after weaning, and monthly after that until six months old.

Does an indoor cat need worming at all?

Yes, just less often. A cat that never goes outside can still pick up worms — through raw meat, through fleas, or through eggs carried in on shoes and clothing. Of the cats found to be infected with roundworm, roughly one in five was kept strictly indoors according to their owner. Treating or testing a faeces sample once or twice a year is the advice.

What do fleas have to do with worms?

Fleas carry tapeworm. A cat that grooms itself and swallows an infected flea takes the tapeworm in with it. That is why worming belongs with any flea problem, even if your cat was wormed recently. Treat the house as well: most of the fleas are not on the cat but in rugs, beds and crevices.

Can I test instead of worming?

Yes. Testing a faeces sample at the same frequency is an equal alternative to treating blind: you have a sample examined and only treat when something is found, which avoids unnecessary medication. Which product your cat needs and at what dose is always for your vet to decide — and never use a product meant for dogs, because some of those are poisonous to cats.

What this planner is based on

The frequencies and the kitten schedule come from ESCCAP Benelux and the Dutch LICG, both checked on 16 August 2026. Every figure in this planner appears verbatim in one of those two sources — and where the source gives no figure, neither does the planner. For a cat that hunts a lot, for instance, they only say more often may be needed in consultation with your vet; so you read ‘at least 4×’ above with that referral attached, rather than a precise-looking number we made up. What it deliberately does not do is name products or doses — that is for your vet, and it depends on your cat’s weight and on which worm you are treating. This is a planning aid, not veterinary advice. If you are unsure, or you can see worms in the faeces or around the anus, ring your practice; take the vet letter along if it helps.