Advanced options
A sinking fund converts predictable annual shocks into a boring standing order: the December that doesn't touch the credit card, the renewal that's just paid. Keep it separate from the emergency fund (that's for the UNpredictable) in an easy-access pot: most banking apps do named "pots" or "spaces" for exactly this. Add your own lines: pet insurance, glasses, school uniform, boiler cover.
What The Sinking Fund Calculator Works Out
- Annual lumpy bills: the four predictable once-a-year costs added together: insurance renewals, MOT and servicing, Christmas and birthdays, and the holiday. The worked example totals GBP 2,700.
- Set aside monthly: the annual total divided by 12, with the weekly figure underneath. GBP 2,700 a year is a GBP 225 standing order into a named pot, and December, renewal month and departure day become withdrawals from money already waiting.
- Why it works: these are appointments rather than emergencies, dated and sized within guessing distance a year out. The emergency fund guards the unpredictable; sinking funds pre-pay the calendar, and raiding one for the other is the classic cross-contamination.
- Extra lines (advanced): two more annual lines for the forgettables that last year's statements surface: pet insurance, vet jabs, boiler cover, glasses, dentist, school uniform and trips. Each is annualised and twelfth-ed with the rest.
- Set aside per payday (advanced): the total divided by 12, 13, 26 or 52 to match monthly, four-weekly, fortnightly or weekly pay, so the standing order can sit the day after payday.
- Already covered (advanced): what is in the pot as months of the year's bills, so you can see how far ahead of the calendar you are.
- Interest the pot earns (advanced): an approximation using the average balance (what is already saved plus half the annual total) at your easy-access rate. Bigger pots suit interest-bearing accounts; the Christmas line suits a regular saver.
- Saved by paying insurance annually (advanced): what paying car insurance in twelve instalments costs at the insurer's APR, often 20% to 40%, which is the renewal-shopping bonus of having the money in hand. The per-line table underneath shows each fund's monthly and payday amount.