Sinking Fund Calculator
Set aside the right amount each month for a known future cost.
Enter your values
ⓘ Live results
Results
- Monthly deposit
- $457.32
- Weekly equivalent
- $105.53
- Total you deposit
- $8,231.70
- Interest earned
- $268.30
- Existing savings at the deadline
- $530.87
Quick answer
A sinking fund spreads a known future cost across the months before it lands: deposit = goal ÷ the future value factor of a monthly savings stream.
PMT = FV × r ÷ ((1 + r)^n − 1)
How to use the Sinking Fund Calculator
- 1Enter the total cost you are saving toward.
- 2Enter how many months you have before the bill lands.
- 3Add any money already set aside and the rate your savings earn.
Worked example
Using the values the calculator loads with:
Inputs
- Amount you need9000 $
- Months until you need it18
- Interest rate on savings4 %
- Already set aside500 $
Results
- Monthly deposit$457.32
- Weekly equivalent$105.53
- Total you deposit$8,231.70
- Interest earned$268.30
- Existing savings at the deadline$530.87
Frequently asked questions
What is a sinking fund used for?
Predictable, lumpy costs — insurance renewals, car tyres, property tax, Christmas — that wreck a monthly budget when they arrive all at once.
Where should the money sit?
In a separate high-yield savings account named for the goal, so it earns interest and is not spent by accident.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.