A monthly instalment measures immediate cash flow. Total interest, repricing risk, loan tenure and ongoing ownership costs decide whether the mortgage remains affordable over time.
What is the monthly payment on SGD 750,000?
Using a standard amortising loan over 25 years, 3.5% gives an estimated monthly payment of SGD 3,755. That is the loan payment, not the home’s full monthly ownership cost.
Compare 3%, 3.5% and 4%
| Annual rate | Monthly payment | Interest over 25 years |
|---|---|---|
| 3% | about SGD 3,557 | about SGD 316,975 |
| 3.5% | about SGD 3,755 | about SGD 376,403 |
| 4% | about SGD 3,959 | about SGD 437,633 |
Moving from 3% to 4% adds about SGD 402 a month and roughly SGD 120,658 of interest if that rate lasted throughout. A floating package will reprice, so this is a stress test rather than a bank quotation.
Twenty years or twenty-five?
20 years at 3.5%
About SGD 4,350 monthly and SGD 293,927 total interest. The monthly commitment is higher, but principal falls faster.
25 years at 3.5%
About SGD 3,755 monthly and SGD 376,403 total interest. Monthly payment is about SGD 595 lower, but interest is about SGD 82,476 higher.
A lender will not look at the payment alone
Approval also depends on income, existing debts, tenure, age, TDSR, MSR where applicable and LTV limits. MoneySense currently describes a 55% TDSR threshold and a 30% MSR cap for applicable HDB and unexpired-MOP EC purchases. The lender makes the final decision.
Four costs beyond the instalment
- Upfront funds: downpayment and stamp duties.
- Ongoing ownership: property tax, maintenance, insurance and repairs.
- Repricing: payments can change after a promotional or fixed period.
- CPF opportunity cost: CPF principal used plus accrued interest is generally refunded when the property is sold.
Run three stress tests before committing
- Add one percentage point to the interest rate.
- Shorten tenure by five years and compare total interest, not just payment.
- Add other debts and ownership costs, then check the household emergency buffer.
Mortgage questions
Why is the bank’s figure different?
A bank may use actual package rates, dates, fees and approval assumptions; this tool uses a standard amortisation model.
Does paying with CPF remove the need for cash?
No. Keep a cash buffer and consider an OA reserve. CPF used for housing also affects retirement savings and the later property refund.
Is early repayment always best?
Not necessarily. Check lock-in periods, prepayment fees, emergency cash and the cost of other debt.
Official planning resources
MoneySense on affordability, TDSR, MSR and LTV · CPF Home Purchase Planner
Written and reviewed by the QuickCalc editorial team. Last reviewed: 8 Sep 2026. Examples assume an unchanged rate and exclude loan fees.