SHIP'S INSTRUMENTS

Plan a purchase

A sinking fund is money set aside every month for a specific purchase so it is paid in cash when the time comes. Enter the price and what you have already, then either what you can save monthly or when you need it.

Plan a purchase

A sinking fund for something you want to pay cash for.

Plan by

How it's calculated

  1. Remaining = price minus what is already saved. With a monthly amount, months to ready = remaining ÷ monthly, rounded up, and the ready date is that many months from now.
  2. With a target month, the required monthly amount is remaining ÷ months until that month, rounded up to the next dollar. The app adds a third view - whether that amount fits inside your actual free cash flow - which needs your budget history.

Worked example

A $2,400 purchase with $400 saved and $200 set aside monthly is ready in 10 months. Flip it around: if you need it in six months, you would have to set aside $334 a month instead.

Frequently asked

What is a sinking fund?

A savings bucket with a name and a purpose - new tires, a trip, next year's insurance premium - funded a little each month so the expense never lands on a credit card. The term comes from the way companies set money aside to retire a bond.

How is this different from an emergency fund?

An emergency fund is for the unknown; a sinking fund is for the known. Tires wearing out is predictable, so it belongs in a sinking fund, which keeps the emergency fund untouched for actual surprises.

What if I cannot afford the monthly amount?

Push the date out, lower the price, or start with a smaller partial goal. The point is to pay cash when you buy, so a later date beats financing it.

Related calculators

Every calculator here runs in your browser and matches the math in the BudgetArk app's Charts tab. Nothing you enter is stored or sent anywhere.

Want it with your real numbers?

In the app, this tool pulls from your actual debts, budget, and accounts - and everything stays on your phone.