The formula
year = monthly costs × 12 + yearly costs · first year = year + one-off costs
Where it comes from
The figure people have in mind before adopting is the food, and food is less than half of it. The rest splits between what you pay every month — grooming, litter, parasite treatments, toys — what you pay once a year — the check-up, the vaccines, boarding during holidays — and what you pay once in the animal’s life: the adoption, the neutering, the microchip and the kit. Mixing the three is what makes the first year look representative when it is not, and the other way round: working from the second year forgets that a large vet bill almost always arrives at the end.
How to work it out by hand
- Add up the costs that repeat every month and multiply by twelve
- Add the ones paid once a year, like the check-up or boarding
- That is the cost of any given year
- Add separately what is paid only once to get the first year
What is worth knowing
What is missing is the unpredictable, which is exactly what weighs most: an emergency, surgery or a chronic treatment in the last years can cost more than several years of running costs put together. Insurance or a savings pot of your own are the two ways to cover it, and it is worth deciding which before you need it.