How to Calculate Home Loan Refinancing in Singapore: A Step-by-Step Guide
Compares your current mortgage with a new rate to show the monthly saving and how long switching costs take to recover.
Property is the largest purchase most Singaporeans make, and stamp duties, loan limits and cash requirements are front-loaded. Small mistakes in these figures can mean a shortfall at completion, so it pays to run the numbers before you commit to an option to purchase.
What you need
- Outstanding loan (S$)
- Current rate (%)
- New rate (%)
- Remaining tenure (years)
- Switching costs (S$)
Step by step
- Enter the outstanding loan (S$).
- Enter the current rate (%).
- Enter the new rate (%).
- Enter the remaining tenure (years).
- Enter the switching costs (S$).
- The results update as you type, or press Calculate.
- Read the current instalment first, then the supporting figures below it.
The formula
Saving = PMT(current rate) − PMT(new rate); breakeven = switching costs ÷ monthly saving.
Worked example
For example, with these inputs:
- Outstanding loan (S$): 600,000
- Current rate (%): 3.8
- New rate (%): 2.9
- Remaining tenure (years): 22
- Switching costs (S$): 3,000
the calculator returns:
- Current instalment: S$3,356.97
- New instalment: S$3,076.95
- Monthly saving: S$280.02
- Months to recover costs: 10.71 months
A second example
Now change the inputs to:
- Outstanding loan (S$): 750,000
- Current rate (%): 3.8
- New rate (%): 2.9
- Remaining tenure (years): 22
- Switching costs (S$): 3,000
the calculator returns:
- Current instalment: S$4,196.21
- New instalment: S$3,846.19
- Monthly saving: S$350.02
- Months to recover costs: 8.57 months
Practical tips
- Stamp duty is based on the purchase price or market value, whichever is higher.
- Budget for legal fees, valuation, renovation and moving costs on top of the downpayment and stamp duties.
- Seller's Stamp Duty can wipe out the gains on a quick resale, so check your holding period before selling.
- Using CPF for housing reduces what is left for retirement, and you must refund the amount used plus accrued interest when you sell.
Background
Stamp duties are paid upfront. Buyer's Stamp Duty applies to every purchase at tiered rates up to 6%, while ABSD depends on the buyer's residency status and how many residential properties they already own. Sellers who dispose of a property within the holding period pay Seller's Stamp Duty.
Singapore's property market is shaped by cooling measures introduced since 2009, including Additional Buyer's Stamp Duty, loan-to-value limits and debt servicing ratios. These rules are adjusted when the market runs hot, so the numbers you see today may differ from what friends paid a few years ago.
Most Singaporeans live in HDB flats, which can be financed with an HDB concessionary loan at 0.1% above the CPF Ordinary Account rate or with a bank loan. Private property must be financed with a bank loan, and banks offer fixed, floating and SORA-pegged packages.
Related calculations
- Property Downpayment Calculator: Splits the downpayment into cash and CPF and shows the remaining loan.
- Buyer's Stamp Duty (BSD) Calculator: Calculates Buyer's Stamp Duty on a Singapore residential property using the tiered rates from 1% to 6%.
- Additional Buyer's Stamp Duty (ABSD) Calculator: Calculates ABSD by buyer profile and the number of residential properties owned, using the rates in force since 27 April 2023.
- Total Property Stamp Duty Calculator: Adds BSD and ABSD together so you know the full stamp duty bill before you sign an option to purchase.
Want to skip the arithmetic? The free Home Loan Refinancing Calculator does all of this instantly and updates as you type.
Run your own numbers: Home Loan Refinancing Calculator