SG Rate Watch

Savings Account Effective APY Calculator

Updated 25 Oct 2026 · SG Rate Watch Editorial Team
Short answer

Enter your balance, your account's base rate, the bonus rate you realistically qualify for and the balance cap the bonus applies up to. The calculator blends them into one effective APY: base rate on the whole balance, plus the bonus rate only up to the cap.

On this page (4 sections)

The advertised rate on a bonus-interest savings account is rarely what your whole balance earns. This tool blends the base rate and the capped bonus into one honest effective APY — you supply the rates.

Tool

Savings account effective APY calculator

The rate paid on your whole balance before any bonus conditions.

Add up only the bonus tiers you actually meet (salary, card spend, bills…).

Most accounts pay bonus interest only up to a cap; the base rate applies above it.

Effective APY—
Interest per year—
Interest per month—
From base rate—
From bonus (capped)—

Based on MAS — Domestic Interest Rates (context). You enter your own account's rates — we hold no bank rate list. Effective APY is general information, not a recommendation.

How it is calculated

Singapore bonus-interest accounts generally pay a low base rate on your entire balance plus a higher bonus rate on the balance up to a cap:

  • Base interest: balance × base rate.
  • Bonus interest: min(balance, cap) × bonus rate — the bonus never applies above the cap.
  • Total interest: base + bonus, per year.
  • Effective APY: total interest ÷ balance, expressed as a percentage — the single rate your whole balance effectively earns.

Because rates and conditions differ by bank and change often, you enter the numbers from your own account’s latest terms. MoneySense explains how deposit account features work.

A worked example (illustrative)

Balance S$100,000, base rate 0.05% on everything, bonus 2.00% on the first S$75,000:

  • Base = 100,000 × 0.05% = S$50.
  • Bonus = 75,000 × 2.00% = S$1,500 (the other S$25,000 earns only the base rate).
  • Total = S$1,550 a year → effective APY = 1,550 ÷ 100,000 = 1.55% p.a., well below the 2.00% headline.

Limits of this estimate

  • It assumes you meet the bonus conditions every month; miss one and the bonus for that month usually disappears.
  • It uses simple annual interest and does not model mid-year balance swings or tiered sub-caps that some accounts layer.
  • It is not a product comparison — it holds no bank rates. Check your bank’s current terms and caps, and compare neutrally.

Sources

  1. Domestic Interest Rates (savings/deposit rate context) — Monetary Authority of Singapore (as of October 2026)
  2. Understanding financial products (deposit accounts) — MoneySense (MAS) (as of October 2026)