Savings
Sinking Fund Planner
Spread the bills you know are coming (car repairs, holidays, insurance) into one monthly set-aside, so they stop landing on a card.
Leave a cost at $0 to skip that line. Months are whole months until the bill is due.
Per expense
- Car repairs$1,200, 10 months away$100.00/mo
- Holidays$900, 2 months away$450.00/mo
- Insurance premium$1,100, 6 months away$133.34/mo
- Back to school$400, 9 months away$44.45/mo
What this means
Setting aside $727.79 a month covers the $3,100 still ahead of you on these bills, each one on its own schedule. Holidays comes first, in 2 months, so that line needs the most attention right now.
These costs aren’t emergencies. You know they’re coming, just not every month. Giving them their own pot keeps your emergency fund for the things you can’t see coming, like a layoff or an ER visit, so it’s still there when one shows up.
These are estimates to help you think, not personalized legal, tax, or investment advice, and not a promise of any result.
This calculator takes the bills that don't come every month (car repairs, the holidays, an insurance premium, back-to-school) and turns them into one steady monthly amount. For each one, enter what it will cost, what you've already set aside and how many months until it's due. It shows the monthly set-aside for each, the total, and which one is coming first.
Why it matters: most budgets are built around monthly bills, so the once-a-year ones show up as surprises even though everyone saw them coming. A sinking fund sets money aside for them a little at a time, so they get paid from the pot built for them and not from a credit card or your emergency fund.
How to use it
List what's coming
Go back through last year's bank statements for the costs that hit once or twice: premiums, registration, holidays, birthdays, school supplies, car maintenance. Enter up to five, with what each one will cost.
Enter what's set aside and when it's due
For each, enter anything you've already put away and the whole months until the bill lands. A bill due this month shows separately, since there are no months left to spread it over.
Set up the total as one transfer
The total is the amount to move each month. One automatic transfer on payday into a separate savings account, tracked by line, keeps it simple.
Behind the numbers
Why it's not the emergency fund
An emergency fund is for the costs you can't see coming: a layoff, an ER visit, a sudden repair. Holiday gifts and an annual premium aren't that. You know they're coming. Paying them from the emergency fund quietly drains it, so when a real emergency shows up, the cushion is thinner than you think.
Each bill on its own schedule
A bill due in two months needs a bigger slice now than one due in ten. The calculator spreads each one over its own months, so the near ones get funded in time. The total drops as the near-term bills get paid and fewer are left.
Rounded up on purpose
Each monthly amount is rounded up to the cent, so the line is never a few cents short on the day the bill arrives. No interest is assumed, which keeps every amount on the safe side.
The math behind it
For each bill: what's left to save = cost − what's already set aside. Monthly set-aside = what's left ÷ months until it's due, rounded up to the cent. The total is the sum of every line. Next due is the bill with the fewest months left.
Worked example
An insurance premium of $1,100 due in 6 months with $300 already set aside leaves $800 to go. $800 ÷ 6 is $133.33, rounded up to $133.34 a month. Add car repairs ($1,000 to go over 10 months, $100), holidays ($900 over 2 months, $450) and back-to-school ($400 over 9 months, $44.45), and the total is $727.79 a month.
Divide by 12 for the yearly ones
For a bill that comes once a year, start setting aside one-twelfth of it the month after you pay it. A $1,200 premium is $100 a month, and next year's bill is covered before it arrives.
Common questions
What is a sinking fund?
Money set aside a little at a time for a specific cost you know is coming. The name comes from old bond finance, where a company put money aside each year to pay off a debt. Here it's just a dedicated pot for the bills that don't come monthly.
Where should I keep sinking fund money?
A separate savings account works well, ideally one that's easy to reach but not linked to your debit card. Some banks let you split one account into labeled buckets, which matches this calculator's lines.
What if a bill is due this month and I haven't saved for it?
That one has to come from this month's budget, and the calculator shows it separately. Once it's paid, put it back on the list with its next due date, so next time it's covered.
Go deeper
The calculator gives you a number. The Budgeting & Cash Flow Brick teaches you what to do with it, in plain English. And if you’re not sure where to start, the free BrickScore Assessment checks your whole foundation in about 5 minutes.
first the number, then the move