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Sinking fund calculator
Your car insurance arrives once a year. Your budget runs every month. Work out how much to plan regularly for bills that come less often.
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Your result
Enter an amount or try the example.
Calculations and files are created on your device. Reloading clears your inputs.
Keep planning with Kalvo
Keep your annual bills in view.
Bring these bills into Kalvo to see your regular reserve contributions and set reminders before the next due date.
Download Kalvo freeFor iPhone with iOS 26 or later. No account or bank connection.
- Save the CSV file on your iPhone.
- Download Kalvo and open “More → Export & Import”.
- Choose “Import entries” and your saved file. Check the preview before importing.
Import is free within your remaining allowance of 10 recurring bills and 2 reserves. Annual and quarterly bills count as reserves. Additional entries need Pro.
Amounts are not converted between currencies. Select the same currency in Kalvo as you use here.
How to use this calculator
- Enter the full bill amount, rather than your current savings contribution.
- Choose annual, six-monthly, quarterly or two-monthly billing.
- Read your monthly planning amount. Add the next due date if you want to import the bill into Kalvo.
A worked example
€600 a year for car insurance means €50 a month. €120 billed quarterly means €40 a month. Together, that is a €90 monthly reserve and €1,080 in annual costs.
How the calculation works
Turn annual costs into monthly amounts
For annual bills, the formula is bill amount ÷ 12. Divide six-monthly bills by 6, quarterly bills by 3 and two-monthly bills by 2. The calculator adds the unrounded contributions before rounding the displayed total to cents. This keeps the total accurate when several small bills are included.
A regular contribution for predictable bills
Common examples are insurance, vehicle tax, annual memberships and software billed annually. Include predictable bills with a recurring billing frequency. The monthly amount shows the average cost across a complete payment cycle, rather than the amount leaving your bank account this month.
Check the first bill separately
This contribution does not account for money already saved or the months remaining before the first bill. If a €600 bill is due in two months and you have saved nothing, €50 a month will not cover that first deadline. Check that initial shortfall separately. Kalvo also calculates regular reserve contributions; it does not track a savings account balance.
Frequently asked questions
What is a sinking fund here?
A regular monthly planning amount for a bill paid less often than monthly. This tool does not move money or open a savings account.
Can I include several annual bills?
Yes. Add a separate item for each bill and select its actual billing frequency. The result shows individual contributions and the combined total.
Does the due date change the monthly contribution?
No. It sets the bill’s schedule when imported into Kalvo. The contribution depends on the amount and billing frequency.
How do I bring this into Kalvo?
Add due dates and download the CSV file. Import it under “More → Export & Import” in Kalvo. The file contains the full bill amount; Kalvo calculates the monthly contribution from it.