Total Debt Servicing Ratio (TDSR) in Singapore: 5 Mistakes to Avoid
TDSR limits all monthly debt repayments to 55% of gross monthly income when you take a property loan. The maths is not complicated, but a handful of errors come up again and again in this and related property & hdb calculations. Here is what to watch for.
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.
CPF Ordinary Account savings can pay for the downpayment, stamp duties and monthly instalments, but using CPF reduces the money compounding for retirement, and the amount withdrawn plus accrued interest must be refunded to your CPF account when you sell.
1. Ignoring SSD when selling early
Selling within four years of buying (for purchases from 4 July 2025) attracts Seller's Stamp Duty.
2. Using the advertised interest rate for affordability
Banks apply a stress-test rate to TDSR and MSR calculations.
3. Overlooking other costs
Legal fees, valuation, fire insurance, renovation and agent fees all add to the total outlay.
4. Assuming the bank will lend 75%
LTV falls to 45% for a second loan and is reduced further for long tenures or older borrowers.
5. Using the price instead of the higher valuation
Stamp duty is charged on the higher of price or market value.
The correct method
Room for new loan = 55% × income − existing monthly debts.
For example, with these inputs:
- Gross monthly income (S$): 12,000
- Existing monthly debt payments (S$): 800
the calculator returns:
- Total debt allowed (55%): S$6,600.00
- Room left for a new mortgage: S$5,800.00
- Current TDSR: 6.67%
Related calculations
- Property Affordability Calculator: Estimates the biggest loan and property price your income supports under TDSR, using the stress-test rate banks apply.
- Rental Yield Calculator: Measures the return from rent before and after costs such as property tax, maintenance fees and agent fees.
- Home Loan Refinancing Calculator: Compares your current mortgage with a new rate to show the monthly saving and how long switching costs take to recover.
- Property Downpayment Calculator: Splits the downpayment into cash and CPF and shows the remaining loan.
The Total Debt Servicing Ratio (TDSR) Calculator applies the formula consistently, so it is a quick way to double-check your own working.
Run your own numbers: Total Debt Servicing Ratio (TDSR) Calculator