How high-interest savings accounts work: bonus interest criteria, tiered interest and reading the effective rate

A high-interest savings account is a Singapore-dollar savings account that pays bonus interest on top of the base rate depending on whether you meet specified criteria each month, such as crediting your salary, spending on a credit card, paying bills by GIRO, buying the bank's insurance or investment products, or growing your balance. It differs from an ordinary savings account in that the rate is not a single number but a table of criteria against balance tiers; it differs from a fixed deposit in that you can withdraw at any time, but the rate may change every month. The key to reading one is that the advertised "up to x%" holds only when every criterion is met and the balance sits at a particular amount.

Structure: base rate, bonus interest and balance tiers

Almost every high-interest savings account has three components:

Check the basis of calculation too. UOB's page states that base interest is calculated on the end-of-day balance and bonus interest on the monthly average balance (MAB), paid monthly, and notes that interest is lower in February, April, June, September and November because those months have fewer days (source: UOB One Account page, accessed 23 Oct 2026). Banks use either the average daily balance or the monthly average balance, so the same sum can earn different interest in different accounts.

Types of bonus criteria

Criteria that pay a bonus only if you buy insurance or investment products call for particular care. The bonus usually lasts for a limited period, while the policy or investment may run far longer, with its own costs and risks. Do not buy a product you do not need for the sake of a bonus rate; whether you need it should be assessed on its own.

Three banks' terms in the same format

The following extracts from the three banks' websites (accessed 23 Oct 2026) are set out in the same format purely to show how to read them. They are not a ranking or a recommendation, and terms may change at any time.

The three structures differ widely. UOB centres on card spend plus salary and covers a higher balance; OCBC stacks categories, and its top tier requires buying insurance and investment products; DBS sets tiers by total transactions and number of categories. Which structure suits you depends on the income and spending habits you already have, not on the highest advertised rate.

Working out the maximum effective rate from a published tier table

The effective interest rate (EIR) is the overall annual rate obtained by adding up the interest on each tier and dividing by the total balance. The calculations below use the tier table on UOB One's page (card spend + salary crediting column: 1.00% on the first S$75,000, 2.50% on the next S$50,000, 3.40% on the next S$25,000 and 0.05% above S$150,000) to estimate annual results at different balances. This is only an illustration based on the published table, not the actual result of any account; actual interest is as calculated by the bank.

The table shows two things. First, when the balance is below the tier cap, the effective rate is lower than the advertised maximum. Second, once the balance exceeds the cap, the extra money earns little more than the base rate, which dilutes the overall effective rate. A common approach is therefore to keep in a high-interest account only the portion that is within the bonus cap and also serves as an emergency fund or short-term float, and to place the rest in fixed deposits or government securities.

Where newly arrived foreigners often get stuck

Most bonus criteria are designed around local income and local spending, and foreign professionals who have just arrived in Singapore often run into the following:

1. Salary credited the wrong way: UOB states that salary must be credited by GIRO, PayNow or FAST with the "SALA" transaction code; cash deposits, cheques, transfers from personal accounts and overseas remittances do not count. If an employer pays from overseas or by an ordinary transfer, the payment may not be recognised as salary.
2. Salary thresholds: UOB requires at least S$1,600 a month and OCBC at least S$1,800; if your first salary credit falls across a month-end, you may not qualify for that month.
3. Credit card not yet approved: card spend criteria require a specified credit card, and approval for new arrivals may take time or require a record of income; approval is at the bank's discretion.
4. Source of funds: large sums remitted from overseas may prompt a request to explain where they came from. This is part of account opening and compliance, and requirements are set by each bank.
5. Time-limited rates ending: OCBC's current 4.70% top tier includes a time-limited boost to the Save category (until 31 Dec 2026); after the boost ends, the standard maximum is 4.45%, so the rate you see when opening the account may not last.

Fees, minimum balances and deposit insurance

MoneySense suggests asking three things before opening an account: what the minimum balance is, what the fall-below fee is, and whether there is a minimum holding period or early closure charge (28 Sep 2026). In the table above, the three banks' fall-below fees range from S$2 to S$5 a month, and UOB also charges S$30 for closing the account within 6 months. For newly opened accounts with modest balances, a fall-below fee can wipe out most of the interest.

On deposit insurance, a high-interest savings account is an ordinary Singapore-dollar savings account and is covered when held with a DI Scheme member bank, but it is aggregated with your other Singapore-dollar deposits at the same bank (fixed deposits, current accounts, SRS cash deposits and so on), up to S$100,000 per depositor per member bank (source: SDIC Deposit Insurance FAQs, accessed Oct 2026). OCBC 360's high-balance category, for instance, requires an average daily balance of S$250,000, at which point part of the money is already above the deposit insurance limit and you will need to weigh that yourself; see What protects your money.

What to look at when comparing with fixed deposits and T-bills

When comparing a high-interest account with fixed deposits or T-bills, put them on the same basis first, or you are likely to overestimate the return:

• Use the effective rate, not the maximum rate: estimate the EIR from your real balance and the criteria you can reliably meet;
• Use the whole balance, not just the bonus tiers: if your total reserve exceeds the bonus cap, count the excess at the base rate;
• Use the whole year, not one month: criteria are assessed monthly, and if card spend falls short or salary arrives late in a given month, that month's bonus is lost;
• Include costs: fall-below fees and any extra spending incurred to meet criteria;
• Liquidity differs: a high-interest account can be drawn on at any time, a fixed deposit withdrawn early may lose all its interest, and a T-bill can only be sold on the secondary market before maturity.

For the full comparison of tools, see the like-for-like comparison; for arranging cash layers, see the 15-point checklist.

Terms and rates in this article are public examples as of 23 Oct 2026. Banks may change them at any time; the banks' websites and account terms prevail. If you would like this interpreted for your own circumstances, you can register your needs through the contact details on this site.