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Sinking Funds in Australia: How to Stop Rego, Insurance and Christmas Wrecking Your Budget

Most budgets don't fail because of the weekly shop. They fail because of the bills that turn up once or twice a year: car registration, insurance renewals, the school excursion, a dentist visit, and Christmas. Because they're not regular, they're easy to forget, and when they arrive they land on a credit card. A sinking fund fixes that.

This is general information only. Adapt it to your household.

What is a sinking fund?

A sinking fund is money you set aside, little by little, for a cost you know is coming. Instead of finding the full amount in one pay, you save a small piece every payday so the money is waiting when the bill arrives. It's different from an emergency fund. An emergency fund is for things you can't predict, like a job loss or a broken fridge. A sinking fund is for things you can predict, even if you'd rather not think about them.

Which costs need a sinking fund?

Go through the last 12 months of bank statements and pull out every cost that isn't weekly, fortnightly or monthly. Common ones in Australian households:

• Car registration and compulsory third party insurance
• Car, home and contents insurance renewals
• Car servicing, tyres and repairs
• Health costs not covered by insurance: dental, optical, physio
• School costs: uniforms, books, excursions, camps, voluntary contributions
• Kids' sport registrations and gear
• Christmas and birthdays
• Annual subscriptions and memberships
• Holidays and school-holiday activities
• Pet costs: vaccinations, vet visits, registration
• Council rates or strata levies if you own
• Professional memberships or licences for work

Step 1: Estimate each cost

For each item, write what it cost last year. If you're not sure, use a sensible estimate and round up. It's better to overestimate and have money left over than to come up short.

Step 2: Work out the per-pay amount

Divide each yearly cost by how many paydays you have before it's due. If you're paid fortnightly and the bill is a year away, divide by 26. If it's due in four months, divide by the number of paydays between now and then, roughly 8 or 9. That's how much to put aside each payday.

When you add up all your per-pay amounts the total can look scary. That's normal. These costs were always there; you were just paying them in lumps. Seeing the real number is the point.

Step 3: Decide how many accounts to use

You have a few options:

• **One savings account for everything.** Simple. Keep a spreadsheet that tracks how much of the balance belongs to each fund.
• **Separate accounts per goal.** Many Australian banks let you open several savings accounts or "buckets" in their app and name them. Seeing "Rego" with its own balance is motivating.
• **A mix.** Separate accounts for the big ones like Christmas and car, and one shared account for the rest.

Look for an account with no monthly fees. Interest is a bonus, but convenience and no fees matter more for sinking funds.

Step 4: Automate on payday

Set up an automatic transfer the same day your pay lands. If the transfers happen without you thinking about them, the system works even in a busy fortnight. Review the amounts every few months as costs change.

Step 5: Spend from the fund, guilt free

When the rego bill arrives, pay it from the rego fund. That's what the money is for. Many people feel uneasy watching a savings balance go down, but a sinking fund is meant to be spent. The win is that your everyday budget doesn't take a hit.

What if you're starting late?

If a big bill is only a few weeks away and the fund is empty, don't give up on the idea. Cover that bill as best you can, then start the fund for next time. You can also ask some providers to split the payment. Many insurers let you pay monthly, though sometimes at a slightly higher total cost, so check before you switch.

For rego, several states offer shorter registration periods, such as three or six months, which can make the payments more manageable. Check your state's transport authority website.

Sinking funds and Christmas

Christmas is the most common sinking fund in Australian households, and for good reason. It's the same date every year, yet it surprises people every December. If you're paid fortnightly and start saving in late January, you have about 24 or 25 paydays to spread the cost over. Starting in late October gives you only a handful, so be realistic about this year and set up next year's fund in January. Our Christmas on a budget checklist can help with this year.

Sinking funds and three-pay months

If you're paid fortnightly, you'll get three pays in a month twice in most years. Many people send part or all of that extra pay to their sinking funds, which can quickly top up a fund that's behind.

Keep it simple

You don't need twenty funds on day one. Start with the three costs that hurt most last year. For many families that's car, Christmas and school. Add more once the habit is set.

Tools that help

The Budget Planner Bundle and Savings Goals + 52-Week Challenge spreadsheets track several goals in one place. Slate Money HQ has savings goals built in and works offline in your browser. If you're new to budgeting, start with our fortnightly budget for beginners.

A worked example without the guesswork

Say last year your car rego, car insurance and one service together came to a figure you can find on your statements. Add them up, divide by 26, and that's your fortnightly car fund transfer. Do the same for school costs and Christmas. Three transfers, set up once, and next year those bills stop being emergencies. Keep a note of the date each bill is due beside the fund so you can check you're on track.

FAQ

General information only, not financial or tax advice. Check ato.gov.au or a registered tax agent for your situation.