How bonus savings accounts work for the bank

"Earn 5% on your savings!" It's on the bank's website, in the app and at the bus stop. But that big number is only part of the story. Whether you actually get it depends on what you do with your account every single month.

Bonus savings accounts are built with a lot of care. Here's how they work, who they work best for, and how to make sure one works for you.

Why your bank wants your savings

When you put money in a savings account, you're lending it to the bank. The bank lends that money out again, as home loans, car loans and business loans, at a higher rate than it pays you.

Savings from people like you are a low-cost, steady source of money for a bank. Banks rely on household deposits for close to 30% of their funding, says the ACCC's 2023 inquiry into bank deposits. The rules banks must follow treat everyday savings as more stable than money borrowed from big investors, so the banks want as much of it as they can get. And they want it to stay.

Here's the gap in plain numbers. The typical base rate on a bonus saver is 0.10%. Miss the conditions every month and $10,000 earns you about $10 a year. The typical variable home loan rate is 6.44%. On $10,000, that's about $644 a year in interest for the bank. That isn't all profit, because banks have other costs too. But it shows why your savings matter so much to them.

The headline rate gets you in the door

A bonus saver pays two rates added together:

• The base rate, which you always get.
• The bonus rate, which you only get in months you follow the rules.

The ad shows the two added up. Right now the typical bonus saver shows 5.00%, but its base rate is just 0.10%. When rates went up in 2022 and 2023, the ACCC found that the bigger headline rates often came from higher bonus and intro rates, not higher base rates. The Reserve Bank has since seen some banks cut their base rate while leaving the bonus alone.

The bonus has to be earned every month

We read the conditions on all 111 bonus accounts that 64 banks publish. Here's what they ask:

• 63% want you to put money in each month, typically at least $100.
• 48% say no withdrawals, or only a few.
• 16% want your balance to grow every month.
• 7% want you to use a card for purchases.

60 of the 111 ask for two or more of these at once. Miss any one and you get only the base rate for that month.

Lots of accounts miss out

The ACCC looked at bonus accounts in the first half of 2023. In a typical month, 71% of them didn't get the bonus.

But those accounts held only 24% of the money. People with bigger balances were much more likely to meet the rules. The Reserve Bank found something similar in 2024: about four-fifths of the money in these accounts earned the bonus.

So the bonus mostly goes to people who can put money in and leave it there, every month. If money is tight and you sometimes need to dip into your savings, you're the one most likely to miss out.

It adds up. The ACCC gave an example: start with $5,000 and add $200 a month. Meet the rules every month and you'd earn about $328 in a year. Never meet them and you'd earn about $18.

Intro rates end quietly

Some accounts start with a high "intro" rate for new customers. Right now 26 accounts have one, typically for 4 months. When it ends, the rate drops, often to a very low base rate.

Many people don't move their money when that happens. The ACCC found that eight months after intro offers ended, about half the money was still sitting in those accounts.

Banks count on you staying put

The ACCC said banks know their customers are "sticky", and they work to keep them that way. In three years, only 16% of people moved their main savings account to another bank. Once your money is in, the bank knows it will probably stay.

What's changing

The ACCC asked banks to warn customers before they miss a bonus, and to publish how many customers actually get it. It also asked them to say clearly what rate you'll get when an intro offer ends. In June 2024 the government said it would make banks tell you when your savings rate changes. When we checked in October 2026, we couldn't find these rules in law yet. So don't wait for a warning. Ask your bank if it can alert you before you miss a bonus, and turn it on if it can.

How to make the bonus work for you

• Set up an automatic transfer for the day after payday, for at least the amount the bonus needs. Then you can't forget.
• Keep a separate everyday account for spending, so you never need to withdraw from your saver.
• Check last month's interest on your statement. If it's tiny, you missed the bonus. Find out why.
• Put a reminder in your calendar for the day an intro rate ends.
• If you often dip into your savings, look at the base rate, not the headline. An account with no conditions and a steady rate might pay you more in real life.

You can see the base rate, the bonus and every condition for each bank's accounts on our savings accounts page. It's updated every night from what the banks themselves publish.

Sources: ACCC, Retail Deposits Inquiry final report (December 2023); Reserve Bank of Australia, Bank funding and the recent tightening of monetary policy (April 2024) and Bank funding in 2024 (April 2025); the Treasurer, Helping Australians get a better deal on banking products (June 2024); every bank's product data under the Consumer Data Right, as at 16 October 2026.