Fixed deposit interest in Singapore is worked out on the amount you place, at the yearly rate, for the part of a year the deposit runs. The formula is simple, but two things trip people up: rates are always quoted per year, and a term is counted in days, not neat fractions of a year.
This guide shows the fixed deposit interest calculation step by step, with figures from rates published on 13 November 2026.
The Fixed Deposit Interest Calculation Formula
Interest = amount placed × yearly rate × (length of term ÷ one year)
For a 12-month deposit, the last part is 1. For six months it is about 0.5; for three months about 0.25.
Example: S$50,000 for 12 months at 1.90% a year, Hong Leong Finance’s online promotional rate for S$20,000 and above at the time of writing (November 2026).
- $50,000 × 1.90% × 1 = $950 at maturity.
That is simple interest: the rate is applied to the original $50,000 only, for the whole term.
Rates Are Per Year, Even for Short Deposits
A promotional “2.20% for 6 months” does not pay 2.20% of your money. It pays 2.20% a year, for half a year.
Example: CIMB’s online 6-month rate of 2.20% at the time of writing (November 2026), on S$10,000.
- $10,000 × 2.20% × 6/12 = $110, about 1.10% of the amount over the six months.
The same applies to odd tenors. Hong Leong Finance’s 2.08% for eight months on S$20,000 earns about $20,000 × 2.08% × 8/12 = $277.
The short version: Multiply the amount by the yearly rate, then by the share of a year the deposit runs. A short deposit at a high yearly rate can earn less in dollars than a longer one at a lower rate.
Counting Days
A deposit runs from its value date to its maturity date, and the bank’s deposit terms set how it counts days and the length of a year. Our examples count actual days over a 365-day year as an illustration; check your bank’s terms for its own method.
Example: S$50,000 for six months at 1.85% a year (Sing Investments & Finance’s online rate for $10,000 and above).
| Method | Calculation | Interest |
|---|---|---|
| Months | $50,000 × 1.85% × 6/12 | $462.50 |
| Days (182-day term, 365-day year) | $50,000 × 1.85% × 182/365 | $461.23 |
The difference is small, but it explains why a bank’s figure rarely matches a rough calculation to the cent.
The start date matters too. UOB says placement instructions sent outside its placement hours are processed the next business day, and interest accrues from that value date.
When Interest Compounds
Within a single term, interest is not added to the principal. Compounding happens only when you renew with principal plus interest, so the next term earns interest on a bigger sum. MoneySense suggests checking whether your rollover covers principal only or principal with interest.
Example: one 12-month deposit or two 6-month deposits? S$50,000, rates assumed unchanged at renewal (illustration only):
| Option | Calculation | Interest after a year |
|---|---|---|
| 12 months at 1.85% | $50,000 × 1.85% | $925.00 |
| 6 months at 1.85%, renewed with interest for another 6 months | Two terms of 182 and 183 days | $929.28 |
| 12 months at 1.95% | $50,000 × 1.95% | $975.00 |
Compounding adds about $4 here. A higher 12-month rate adds $50. The rate matters far more than the compounding, and a renewal may not get the same rate: many deposits roll over at the much lower board rate.
Over several years compounding adds up. $50,000 renewed yearly at an assumed 1.90%, with interest added, grows by about $2,904 over three years, against $2,850 if you took the interest out each year. Model longer periods with our compound interest calculator.
Which Amount Sets the Rate
Some banks pay different rates by amount band. DBS goes further: it sets the rate on your total SGD fixed deposit balance, not each placement. On its 13 November 2026 board rates, a total under $20,000 earns 1.00% for 12 months, but $20,000 or more earns 0.05%.
So before calculating, check which band your amount falls into, and whether the bank looks at the placement or your total.
Comparing a Fixed Deposit With a Savings Account
Savings account interest depends on your balance over time and any bonus conditions you meet, while a fixed deposit pays on a fixed sum for a fixed term. To compare like with like, work out the yearly dollar figure for each. Our savings account interest calculator does the savings side; then compare it with the fixed deposit formula above. For a wider comparison, see fixed deposits vs savings accounts vs money market funds.
What To Do Next
- Use the formula on this month’s FD rates at your own amount and tenor.
- Check the maturity amount before you confirm. HSBC’s app, for example, shows the interest amount before you place.
- If you plan to renew, check the rollover rate and whether interest is added to the principal.
- Remember the interest is tax-free for individuals, according to IRAS.
