Sinking Fund Calculator
A sinking fund is money you set aside each month for a specific planned expense — a vacation, car repair, new appliance, or annual insurance bill. Save consistently now so the money is ready when the expense arrives, debt-free.
Enter your savings goal, target date, and any existing savings to see exactly how much to set aside each month, plus a full savings schedule.
| Month | Deposit | Interest | Balance |
|---|
How a Sinking Fund Works
A sinking fund is one of the simplest and most effective tools in personal finance. You identify a future expense with a known cost and a known date, divide the cost by the number of months you have, and save that amount every month. When the expense arrives — the car insurance renewal, the family vacation, the new laptop — you pay cash from the fund instead of putting it on a credit card or depleting your emergency fund.
Sinking Fund vs. Emergency Fund
These two accounts solve different problems and both belong in a solid financial plan. An emergency fund covers the unexpected — a job loss, an unplanned medical bill, a burst pipe. A sinking fund covers the expected — expenses you know are coming but that aren't part of your monthly budget. The key insight: most "emergencies" are actually just poorly planned regular expenses. A $1,200 car insurance bill is not a surprise if you've been saving $100/month all year.
| Category | Typical Target | Timeframe | Monthly Savings |
|---|---|---|---|
| Annual car insurance | $1,200 | 12 months | $100 |
| Vacation | $3,000 | 12 months | $250 |
| Home maintenance | $5,000 | 24 months | $208 |
| Holiday gifts | $800 | 10 months | $80 |
| Car replacement | $15,000 | 36 months | $417 |
Running Multiple Sinking Funds at Once
You don't have to choose between funds — you can run five or ten simultaneously. Many people use a high-yield savings account with sub-account "buckets" (available at banks like Ally or Marcus), or separate accounts with clear labels. The math is simple: if your car insurance fund needs $100/month, your vacation fund needs $250/month, and your home repair fund needs $150/month, you need to budget $500/month total across those three categories. Calculate each fund separately, then sum them to see whether you have enough monthly cash flow.
Where to Keep a Sinking Fund
Keep sinking funds in a high-yield savings account (HYSA), not a checking account. With rates of 4%–5% APY currently available at online banks, even a 12-month fund earns meaningful interest. Avoid putting short-term sinking funds in CDs with lock-up periods — if the expense comes earlier than expected, you don't want an early withdrawal penalty. And avoid the stock market for any sinking fund with a target date under 3 years: you need a predictable balance, not one that could drop 20% right when you need to spend it.
Sinking Fund Formula
If your savings account pays no interest, the monthly amount is simply: Goal ÷ Months. If your account earns interest at a monthly rate r, the exact formula is: Monthly Payment = FV × r / [(1+r)^n − 1], where FV is the target future value and n is months. For a $3,000 goal in 12 months at 4.5% APY (r = 0.375% per month), you need to save about $244/month instead of $250 — the interest contribution is small but meaningful for longer-horizon funds.
Once your sinking fund goal is met, consider where the money goes next. The Savings Goal Calculator can help you plan longer-term targets, and if you're building toward financial independence, try the Emergency Fund Calculator to make sure your safety net is sized correctly alongside your sinking funds.
Frequently Asked Questions
What is a sinking fund?
A sinking fund is a dedicated savings account where you set aside a fixed amount each month for a specific planned future expense — vacation, car maintenance, holiday gifts, home repair, or annual insurance. You know the expense is coming, so you save for it in advance rather than reacting to it with debt or by draining your emergency fund.
How much should I put in a sinking fund each month?
Divide your goal amount by the number of months until you need it. For $3,000 in 12 months: $3,000 ÷ 12 = $250/month. If your savings account earns interest, you can save slightly less — use this calculator to find the exact amount with compound growth included.
What is the difference between a sinking fund and an emergency fund?
An emergency fund covers unpredictable expenses (job loss, medical emergency, urgent repairs). A sinking fund covers predictable future expenses you know are coming. Both serve different purposes — ideally you run both simultaneously. The emergency fund is a liquid buffer of 3–6 months of expenses; sinking funds are targeted amounts for specific upcoming costs.
Where should I keep a sinking fund?
In a high-yield savings account (HYSA) earning 4%–5% APY. Keep it separate from your checking account (so you don't accidentally spend it) and from your emergency fund (for clarity). Avoid CDs with penalty lock-in periods and avoid the stock market — you need a stable, accessible balance.
How many sinking funds should I have?
As many as you have recurring planned expenses. Common ones: car maintenance, home repair, travel, holidays, insurance premiums, medical/dental, electronics, clothing. Most people benefit from 3–8 simultaneous sinking funds. Budget for all of them together and make sure the combined monthly amount fits your cash flow.
Related Calculators