An expense is not unexpected simply because it does not occur every month. Annual insurance, tuition, car maintenance and December gifts have an approximate date and can be planned for. A sinking fund spreads that future cost across several months.
Create a twelve-month calendar
Review the previous year and note quarterly, half-yearly and annual payments. Include the smaller amounts that often coincide: servicing, fees, school supplies, celebrations or renewals. For each expense, estimate the date, amount and degree of certainty.
Do not use the lowest figure when the cost varies. Add a reasonable margin based on past experience and update it when you receive a renewal notice. Banco de España’s family-budget guidance recommends organising bills and due dates; that calendar is the starting point.
Turn each expense into a monthly contribution
Subtract what you have already set aside and divide the remainder by the months available. If a €400 payment is due in four months and you have saved nothing, the indicative contribution would be €100 a month. If that does not fit, adjust the target, look for alternatives or start earlier in the next cycle.
Keep each fund clearly identified even if the money is held in one account. Do not confuse it with an emergency fund: the latter covers unexpected situations, while a sinking fund covers known costs.
Review after paying
Record the actual amount, compare it with your estimate and recalculate the next due date. If money is left over, decide whether it should remain as a cushion or be reassigned. Automating a contribution after your income arrives reduces effort, but it should still allow pauses when your liquidity changes.
Kinset can show which payments appear once or twice a year and how much you would need to set aside each month. The decision to separate the money, and the product used to hold it, should reflect your needs for access and security.
This content is educational and does not recommend any specific financial product.