Term Deposit Interest Calculator

Enter your deposit, the interest rate, the term in months and how often interest is paid to see the interest you would earn and your balance at maturity. The figures use the same calculation as the interest earned column in our Term Deposits tables, so what you see here lines up with the deposits you compare. This is general information, not advice.

Starts on the best rate we track for your amount, term and how interest is paid, from a term deposit anyone can open. Type the rate you were offered to use it instead, or clear the field to go back to ours.

Any term from 1 to 60 months.

Common terms
Interest paid

Depositing $10,000 for 1 year at 5.60% p.a., interest paid at maturity

That is the best rate we track for $10,000 over 1 year with interest paid at maturity, from a term deposit anyone can open (Community First Bank 12 Month Term Deposit Special).

Interest earned
$560
Balance at maturity
$10,560
Compare Term Deposits

Estimate only, at the rate shown for the whole term. Interest paid at maturity is simple interest. Interest paid monthly, quarterly or annually is assumed to be added to the deposit, so it earns interest in turn; paid out to another account instead, the total is a little lower. Fees, tax and early withdrawal are not included. This is general information, not advice.

Deposits with an authorised deposit-taking institution are covered by the Australian Government’s Financial Claims Scheme up to $250,000 per account holder, per institution. Note that institutions sharing one banking licence share a single $250,000 cap.

How we calculate this

The formula

I = P × r × t
I
the interest earned over the term
P
the amount you deposit
r
the interest rate per year, as a decimal (4.50% is 0.045)
t
the term in years (months ÷ 12)
n
how many times a year interest is paid (12 monthly, 4 quarterly, 1 annually)
k
the number of whole payment periods in the term

That is interest paid at maturity. When interest is paid monthly, quarterly or annually, we apply:

  • I = P × (1 + r ÷ n) to the power of k, minus P
  • any part period after the last payment earns simple interest

What we assume

  • One rate for the whole term. A term deposit’s rate is fixed when you open it, so the rate in the calculator, the best one we track or the one you enter, applies from start to finish.
  • Interest paid during the term stays in the deposit. Each payment is added to the balance and earns interest in turn. If it is paid out to another account instead, the total is a little lower.
  • Only whole periods are paid. A 5 month deposit paying quarterly is paid once, and the last 2 months earn simple interest, which is how banks pay and keeps the estimate on the cautious side.
  • Same calculation as our tables. The interest earned column in our Term Deposits tables runs this calculation on each deposit, at its own rate for the term and its own payment frequency.
  • Not included. Tax on the interest, fees, and the reduced rate or notice period that usually applies if you withdraw before maturity.

A worked example

$20,000 deposited for 12 months at 4.50% p.a.

  1. Term in years12 ÷ 121
  2. Interest paid at maturity$20,000 × 0.045 × 1$900.00
  3. Interest paid monthly instead$20,000 × (1 + 0.045 ÷ 12) to the power of 12, minus $20,000$918.80

Figures above are rounded for reading, so a line can differ by a dollar from the exact arithmetic. The calculator itself works to full precision.

The deposit earns $900 paid at maturity, or $919 paid monthly, $19 more because each month’s interest earns interest for the rest of the term.