The choice between an HDB Concessionary Loan and a bank loan is one of the most consequential financing decisions an HDB buyer makes — and one of the least understood. HDB loan rate is pegged at 0.1% above CPF OA rate (currently 2.6%), while bank loans fluctuate with SORA. When SORA is low, bank loans appear cheaper. When SORA rises, the HDB loan — which cannot exceed 2.6% — becomes the cost-effective option. The correct comparison depends on where rates are heading over your loan tenure, not just where they are today.
The single most important number this calculator reveals is the total interest cost differential over your full loan tenure. A $400,000 HDB loan at 2.6% over 25 years costs $134,800 in total interest. The same loan at a bank rate of 3.5% costs $193,200 — a $58,400 difference. But at 2.5% (a competitive bank rate in a low SORA environment), the bank loan costs only $126,100 — $8,700 less than HDB. The total interest comparison over the full tenure, not the monthly payment comparison, is the correct decision framework.
The most common mistake buyers make is focusing only on the current monthly repayment difference. Bank loans may be $100–$200 cheaper per month at current rates — but carry refinancing risk, rate reset risk, and potentially higher lock-in penalties. HDB loans cannot be prepaid without penalty for 1 year, but offer full flexibility after that. A buyer who takes a bank loan for a $100/month saving and then faces a SORA spike of 2% may find their monthly repayment increases by $400 — erasing years of savings in a single rate cycle.
Use this calculator alongside the Mortgage Calculator and the Affordability Stress Test to pressure-test your HDB loan decision against rate scenarios.