How it works
A multi-goal sinking fund plan answers the question single-pot calculators cannot: with one limited monthly surplus and several named targets, how should each dollar split, and when does everything actually land? This planner runs a rolling allocation rather than a static percentage split. The near-term goal — travel here, due in twelve months — takes its mathematically exact payment off the top ($262 on defaults); the remaining $438 divides across the other pots pro-rata by target size, so the $12,000 emergency top-up outpaces the $9,000 car fund. Then the part that matters happens dynamically: whenever any pot reaches its target, its monthly deposit rolls forward to the next open goal, accelerating everything behind it. The simulation tracks all three pots compounding at your APY simultaneously and reports completion months, total interest earned (~$590 on these defaults) and the milestone table. The insight most planners miss is that equal-percentage splits are rarely optimal — hard deadlines deserve exact funding while flexible goals can absorb leftovers, and letting completed pots roll their deposits forward shaves months off the final finish compared with splitting evenly forever. Re-run after any change in surplus, because allocation shares shift non-linearly as deadlines and balances interact.
Formula
Near-term payment = target × r ÷ ((1+r)^D − 1) | Remainder splits pro-rata by target | Completed pots roll their deposit into the next open goal
Tips
- Give only genuinely dated goals hard deadlines; let flexible ones absorb the rolling extras.
- Re-check allocation after every raise — surplus changes move completion months non-linearly.
- Keep pots in labelled buckets of one high-yield account rather than separate banks.
- If a deadline forces an unaffordable payment, extend the date before shrinking other goals.
- Audit pots quarterly; balances drift from reality as purchases happen mid-cycle.
Frequently asked questions
- How do I split my savings between multiple goals?
- Fund dated obligations exactly, then divide the remainder pro-rata by target size. On this planner's defaults, a $700 surplus sends $262 to the twelve-month travel deadline and splits the rest toward the $12,000 emergency pot and $9,000 car fund. Completed pots then roll deposits forward automatically.
- Should I save for emergencies or a car first?
- Price both timelines. Here the emergency top-up and car fund finish within a few months of each other because proportional sharing keeps them roughly synchronized — but if your current car is dying, weight its pot harder. The right order depends on which gap hurts most, not a universal rule.
- How many sinking funds is too many?
- Three to six active pots is practical; beyond that, tracking overhead eats the benefit. Consolidate small irregular expenses like gifts and haircuts into one 'irregulars' bucket. This planner models three pots because that covers most households' genuinely competing priorities at any single moment.
- Do sinking funds earn interest while waiting?
- Yes — modelled monthly here at your APY, worth about $590 across these three pots before all of them close. Interest is allocated per-pot as it accrues, which slightly accelerates early completions. Keep the pots inside a high-yield account, because checking-account interest barely registers at these balances.
- What happens when one goal finishes early?
- Its monthly deposit rolls forward to the next open pot instead of evaporating back into spending — that redistribution is why the last goal finishes months sooner than a static split would allow. The milestone table shows each handoff explicitly so you can verify nothing went missing.