How to Save for Yearly Bills with a Sinking Fund

Most months look roughly the same: rent, groceries, a phone bill and whatever is left for savings. Then March brings the car insurance, June the tax bill and December the presents, and suddenly a normal month needs twice the usual cash. A sinking fund takes those yearly bills and turns them into a small, steady monthly amount.

This tutorial builds a sinking fund in BudgetFlow step by step.

What a Sinking Fund Is

A sinking fund is a separate pot of money where you set aside a fixed share of a known future expense every month. When the bill arrives, the money is already there, so your regular month stays untouched.

An emergency fund covers surprises, while a sinking fund covers expenses you can see coming on the calendar. That is why it works so well: you know the amount and the date, so you only need to divide by twelve.

Here are the yearly bills in our example:

Paid in the month they are due, the holiday alone eats almost half of a 3940 salary. Spread over the year, all five bills together cost about 370 a month.

Step 1: Start with the Monthly Basics

Create a new budget from the budgets list and add the flows that happen every month. Click + Flow on the budget page, type Salary as From and Main Account as To, keep the type Fixed amount, and enter 3940 with the interval monthly. Typing a name that does not exist yet creates it for you.

Add three more flows from Main Account the same way: Rent with 1260, Groceries with 480 and Phone with 39.

Main Account now keeps 2161 a month that no flow uses. The ⚠ next to the budget title points this out as leftover cash. That is fine for now, because the next steps will put it to work.

Step 2: Route the First Yearly Bill Through the Sinking Fund

Every flow in BudgetFlow can pass through several names on its way. That is a multi-step flow, and it is exactly what a sinking fund needs: the money leaves Main Account, waits in the Sinking Fund, and ends up at the bill.

Click + Flow again. Set From to Main Account, then click + Step and type Sinking Fund as the Via name. Set To to Car Insurance. Enter the amount as 684 and pick the interval yearly, because that is how the insurance company bills you.

The result is one flow that reads Main Account → Sinking Fund → Car Insurance: 684 yearly. Every step carries the same amount, so the Sinking Fund shows exactly what passes through it.

Notice that you entered 684 but the chart shows 57. BudgetFlow converts every flow into the interval of the budget view, so a yearly amount appears as its monthly share: 684 divided by 12 is 57. You never have to do that division yourself, and if the insurance goes up next year, you change one number.

Step 3: Add the Other Yearly Bills

Repeat the same flow for the other four bills, each with Sinking Fund as the Via name and the interval yearly:

• Main Account → Sinking Fund → Tax Bill: 1150 yearly
• Main Account → Sinking Fund → Holiday: 1800 yearly
• Main Account → Sinking Fund → Gifts: 420 yearly
• Main Account → Sinking Fund → Car Service: 390 yearly

The Sinking Fund now collects 4444 a year, which is about 370.33 a month. That is the amount you would set up as a standing order from your main account to a separate savings account in your bank. The chart also shows how much of it belongs to each bill, so you can see at a glance that the holiday is the largest part.

Because each bill is its own flow, changing one of them is quick: click its band in the chart to open the flow, adjust the amount and save. The monthly total of the Sinking Fund follows automatically.

Step 4: Send the Rest to Savings

Main Account still keeps whatever is left after rent, groceries, the phone bill and the sinking fund. Instead of calculating that number yourself, let a smart flow do it.

Click + Flow, set From to Main Account and To to Savings, and pick the type Send excess cash. A smart flow has no amount field: it looks at Main Account and sends whatever is left over.

The calculation is 3940 minus 1260, 480, 39 and 370.33, which leaves about 1790.67 for Savings. If your rent rises or you add another yearly bill to the Sinking Fund, the savings amount adjusts on its own, and the ⚠ warning about leftover cash disappears because nothing stays unused in Main Account.

Check the Totals in the Yearly View

The interval select at the top of the budget switches the whole chart between daily, weekly, biweekly, monthly and yearly. Set it to yearly and the yearly bills show the amounts you entered again, while the monthly flows are multiplied by twelve:

• Salary: 47280
• Rent: 15120, Groceries: 5760, Phone: 468
• Sinking Fund: 4444, split into the five bills
• Savings: 21488

This view is a good way to compare the sinking fund with the bills you actually paid last year. If the holiday cost more than 1800, raise the flow and the monthly share updates with it.

Why This Setup Works

Without a sinking fund, the yearly bills compete with your savings in the month they arrive, and in a bad month they compete with your rent. With it, every month carries the same share, and the bill is already covered when it lands.

The multi-step flows keep the picture honest: you see both the total that goes into the Sinking Fund and what each part of it is for. The smart flow to Savings means you only maintain the amounts you know, and the leftover takes care of itself.

You can build this budget yourself in a few minutes, with your own yearly bills as the amounts.