Calculate interest

Calculate interest

Ever wondered how you earn interest on your savings account? Chances are it’s not keeping you up at night, but here’s a simple guide for you to work out your savings potential.

There are three important things used to calculate interest on your cash – the principal, interest rate and time.

1. Principal

The principal is essentially the amount you have in savings to gain interest. It is recommended that households keep about two months of salary as a rainy day fund.

2. Interest rate

This is the rate offered by your financial institution, and is the percentage of your principal that will become interest every year.

  • Simple interest

This is interest paid only on the original amount invested. For example, if you have $5,000 in savings (principal) at a 4 per cent rate for six years, your interest earned will be: $5,000 x 0.04 x 6 = $1,200. However, this assumes that you spend your interest as soon as you gain it, rather than keep it in your savings account.

  • Compound interest

This is described as ‘interest on interest’. The more frequently interest is paid and reinvested into an account, the greater the final return. This is called compounding, which means interest is being paid on the interest reinvested. In other words, if you leave your savings untouched, then they will grow much faster.

For instance, if you invested $10,000 for one year at a 7 per cent per annum, and interest is paid quarterly and reinvested, at the end of the year you’ll have earned $175. That’s because $10,000 x 0.07 x (3 / 12) = $175.

3. Time

How long you save for is just as important in determining your earnings as your interest rate. For example, keeping your cash in a high-rate account for only one year will likely earn you less than if you kept it in a lower-interest account for two years.

  • Other factors

With RateCity’s savings account calculator, you can pinpoint your return with even more accuracy. For example, you can calculate the impact of additional deposits, such as salaries.

So experiment with different scenarios and savings methods to see what kind of difference healthy habits can have on your balance. And when you are done calculating, make numbers into reality by searching online for the best rates on savings accounts.

Did you find this helpful? Why not share this article?

Advertisement

RateCity
ratecity-newsletter

Money Health Newsletter

Subscribe for news, tips and expert opinions to help you make smarter financial decisions

By signing up, you agree to the RateCity Privacy Policy, Terms of Use and Disclaimer.

Today's top savings accounts products

Advertisement

Learn more about savings accounts

How does interest work on savings accounts?

The type of interest savings accounts accrues is called compound interest. Compound interest is interest paid on the initial deposit amount, as well as the accumulated interest on money you have. This is different from simple interest where interest is paid at the end of a specified term. Compound interest allows you to earn interest on interest at a higher frequency. 

Example: John deposits $10,000 into a savings account with an interest rate of 5 per cent that he leaves untouched for 10 years. At the end of the first year he will have $10,512 in savings. After ten years, he will have saved $16,470.

How to make money with a savings account?

Savings accounts make you money by earning interest on your savings. The more money you deposit, the longer you leave it in the account, and the higher the account’s interest rate, the more interest you’ll be paid by the bank or financial institution, and the more your wealth will grow.

To make sure your savings account makes money and doesn’t lose money, it’s important to maintain a large enough minimum balance that the annual interest earned exceeds any annual fees charged on the account.

What are the two types of NAB locked savings accounts?

With a locked savings account in NAB, you can earn bonus interest and learn financial discipline. NAB offers two types of locked savings accounts, each with their own terms and conditions.

The NAB Reward Saver account pays a variable base interest rate of 0.05 per cent per annum and a bonus interest of 0.55 per cent. You’re eligible for the bonus if you make a minimum of one deposit on or before the second last banking day and have no withdrawals in the month.

Meanwhile, the NAB iSaver account provides 0.05 per cent as the standard base interest rate and a fixed bonus margin of 0.55 per cent during the first four months from the date of opening the account. You can park your cash in the account and enjoy unlimited monthly transfers between linked daily bank accounts without impacting the interest rate.

Do I have to claim interest on my savings account?

When you lodge your income tax returns, you must include in the documentation all your sources of income, including bank interest. Your bank will report any interest you earn on the funds in your savings account to the Australian Tax Office (ATO). When the ATO then compares this information with your tax returns,  you also need to have mentioned the interest earned. If there is any discrepancy, you’ll receive a letter from the ATO. 

Avoid this situation by ensuring you receive your bank statement with interest noted. Then declare the interest in your tax returns and pay the tax that’s applicable based on the income tax rate.

You only need to claim your share of the interest earned for joint accounts. If you manage an account for your child and receive or spend money via this account, you will also need to report any interest earned from said account.

What is an ANZ locked savings account?

An ANZ locked savings account locks your money and prevents you from spending. You may use a standard savings account as the account where your salary is deposited. You can then withdraw funds when needed, but aren’t able to make purchases with it. However, this account may not grow much as the continual withdrawing of funds will limit the interest you can earn.

With a locked savings account in ANZ, you know your savings will grow because you can’t access the money. You can also qualify for a bonus when you deposit at least $10 per month and don’t make any withdrawals. To help you with this further you can set up an automatic transfer from your regular ANZ savings or transaction account so you don’t forget to make a monthly deposit.

Your ANZ locked savings account offers you a base interest rate of 0.1 per cent per annum plus an additional bonus interest of 0.49 per cent per year. The interest is calculated daily and credited to your account on the last working day of the month.

Who has the highest interest rates for savings accounts?

As banks frequently change their rates, the most accurate way to know who currently has the highest interest rate is to use a savings account comparison tool.

What is the interest rate on savings accounts?

As banks frequently change their rates, the most accurate way to look at interest rates on savings accounts is to use a savings accounts comparison tool. When you look at the savings rate check what the maximum and minimum rates are. Often banks will offer you a promotional rate for the first few months which is competitive, but then revert back to a base rate which can sometimes be less than inflation. Ongoing bonus rates are often a safer bet as they will keep rewarding you with the maximum rate, provided you meet their criteria

How much money should I have in my savings account?

A good rule of thumb when working out a minimum balance for your savings account is to make sure that you’ll earn more in annual interest on your savings than what you’ll be charged in annual fees.

If you’re saving with a specific goal in mind, prepare a budget so the interest you earn on your deposits will help you efficiently reach this goal. Online financial calculators may be helpful here.

Should I open multiple savings accounts with UBank?

UBank offers customers an opportunity to make the most of their savings by opening multiple savings accounts. Having multiple savings accounts with UBank may be ideal for savers tracking different goals in separate accounts. 

It’s important to note that to earn bonus interest, you will still need to meet the conditions of the UBank savings account every month. If you don’t make these deposits, you will receive the standard interest rate, which is typically lower. 

Keep in mind that you won’t earn bonus interest on your UBank savings account in the month an account is opened and if you open multiple savings accounts with UBank, you'll start earning any bonus interest the following month. 

It's also not yet known how long the special interest rate will hang around for, so please check with your bank for more information. 

Can you direct deposit to a savings account?

Yes. You can make one off payments or set up regular direct deposits into a savings account. This can be organised easily through online banking or by making deposits in a branch. Talk to your lender to find out the easiest way for you to set up direct deposits.

Can you set up a savings account online?

Yes. Several large and small banks offer online applications for savings accounts, and there are also online-only financial institutions to consider.

Online-only savings accounts are often less expensive than other savings accounts, though they may not offer the same flexibility, features, or face-to-face service as more traditional savings accounts.

What is a savings account?

A savings account is a type of bank account in which you earn interest on the money you deposit. This makes it one of the easiest and safest investment tools.

Can I overdraft my savings account?

A lot of savings accounts won’t let you overdraw. Some will allow this feature but you’ll need to apply first. It’s best to read the fine print and check with your lender whether this is a feature they offer. It can be a helpful addition, but as your lender can charge you a fee as well as interest for going into negative numbers, it’s best to avoid overdrafting when possible.

Can you have a joint savings account?

Yes. Joint savings accounts can be useful for two or more people wanting to combine their savings to meet shared financial goals, including spouses, flatmates and business partners.

Some joint savings accounts require all parties to sign before they can access the money. While less convenient, this extra security can help encourage all parties to meet their shared financial goals.

Other joint savings accounts allow any of the account holders to access the money. These accounts can be convenient for financially responsible couples that trust one another implicitly.