The mortgage stress test and debt-servicing ratio
You can have a good salary, a clean credit record and a large deposit, yet still be declined for a mortgage in Hong Kong. The most common reason is that your total monthly debt obligations — including credit cards, car loans, and any guarantees you have given — exceed what the bank considers safe. The formal measure is the debt-servicing ratio (DSR), and until early 2024 the Hong Kong Monetary Authority (HKMA) also required a stress test. That test is now suspended, but banks still apply their own affordability checks, so a borrower can still be rejected purely on affordability grounds.
What is the debt-servicing ratio?
The DSR compares your total monthly debt payments to your monthly income. As of 16 October 2024, the HKMA sets the DSR limit at 50% for all residential and non-residential property, whether for self-use or investment. This means your total monthly debt obligations cannot exceed half of your gross monthly income.
The key point: it is total debt, not just the new mortgage. The bank counts:
- The monthly payment on the mortgage you are applying for (based on the loan amount, term, and an assumed interest rate that the bank sets internally)
- Any existing mortgage payments on other properties you own
- Monthly payments on car loans, personal loans, and credit card balances (typically 3% to 5% of the outstanding balance, treated as a monthly commitment)
- Any guarantee you have given for someone else's mortgage — that loan's full monthly payment is added to your obligations, even if the other party is paying it
If total debt obligations exceed 50% of gross monthly income, the bank cannot lend under standard mortgage terms. This is not a "guideline" — it is the binding regulatory limit imposed by the HKMA.
Why the stress test is no longer a live requirement (but still matters)
From 28 February 2024, the HKMA suspended its prescribed stress test. Previously, banks had to check that borrowers could still meet a 50% DSR limit after a 200-basis-point interest rate rise. That requirement is gone.
However — and this is a point often missed — banks are still required by the HKMA to apply their own credit standards when assessing affordability. In practice, most large Hong Kong banks still apply an internal stress test, often similar to the old one. So:
- You no longer face a regulatory stress test that would impose a stricter DSR limit on a hypothetical rate rise.
- But a bank can still decline you if its internal affordability calculation shows you would struggle if rates rise.
- The bank's internal stress test may also apply a higher assumed interest rate than your actual mortgage rate, reducing your available borrowing capacity.
Therefore, a borrower with a high DSR at current rates — especially if they have other debts — may still be rejected even though the formal stress test is gone.
Worked example: how a car loan or a guarantee reduces your borrowing power
Assume you earn HK$60,000 gross per month and have no other debts. A typical bank offers a mortgage at 4.5% interest over 30 years.
| Scenario | Total monthly debt obligations | Maximum mortgage payment before hitting 50% DSR | Maximum loan amount (approx) |
|---|---|---|---|
| Scenario A: No other debts | 0 | HK$30,000 (50% of HK$60,000) | ~HK$5.9 million |
| Scenario B: HK$4,000/month car loan | HK$4,000 | HK$26,000 (HK$30,000 – HK$4,000) | ~HK$5.1 million |
| Scenario C: Guarantee for brother's HK$15,000/month mortgage | HK$15,000 | HK$15,000 (HK$30,000 – HK$15,000) | ~HK$2.9 million |
| Scenario D: Car loan HK$4,000 + guarantee HK$15,000 | HK$19,000 | HK$11,000 (HK$30,000 – HK$19,000) | ~HK$2.1 million |
Note: Loan amounts are hypothetical at a 4.5% rate, showing the impact of other debts. For current rates, check with your bank.
The difference between Scenario A and Scenario D is HK$3.8 million in borrowing capacity — lost entirely to a car loan and a guarantee. Many borrowers do not realise that a guarantee counts as a full debt obligation, even if the guaranteed person is making all payments on time.
Practical steps to improve your application
If your DSR is too tight, these steps can help — but they require planning:
1. Pay down or fully settle non-mortgage debts
A car loan of HK$200,000 may only cost you HK$4,000 per month, but it reduces mortgage capacity by roughly HK$800,000 (at a 4.5% rate over 30 years with 50% DSR). Paying it off before applying is often the single most effective move.
- Settle credit card balances entirely (banks treat 3–5% of the balance as a monthly commitment).
- Pay off personal loans early, even if there is a penalty — the mortgage benefit usually outweighs it.
2. Remove or reduce guarantees
If you have guaranteed a relative's mortgage and the borrower is in good standing, ask the bank if they will release you as guarantor. Some banks allow this after a few years of on-time payments, especially if the loan-to-value ratio has fallen. Alternatively, the other party may refinance without your guarantee.
- Note: for new applications, the HKMA removed the rule that required a 10-percentage-point cut to DSR and LTV for people with existing mortgages or guarantees. That restriction was lifted on 16 October 2024. But the guarantee still counts as a debt obligation in the DSR calculation, which is the binding limit.
3. Increase income or include a co-borrower with strong finances
A co-borrower's income is added to yours, and their debts are added to yours. This works best if they have no significant existing obligations. A spouse with a clean record and no car loan or guarantee can materially lift the combined DSR ceiling.
4. Extend the mortgage term
Longer terms reduce monthly payments, which lowers the DSR. Most Hong Kong banks offer up to 30 years; some offer 40 years in limited circumstances. This is not always available for older borrowers or for property over a certain age.
5. Choose a lower loan amount or a cheaper property
Obvious, but often overlooked. If your ideal flat costs HK$8 million but the maximum mortgage after DSR is only HK$5 million, you need to find a less expensive property or a larger deposit. The LTV limit at 70% means you need at least 30% down, but DSR is usually the first binding constraint for borrowers with other debts.
What to check next
Before signing any provisional sale and purchase agreement — which commits you to pay stamp duty and penalties if the mortgage falls through — ask your bank for a mortgage pre-approval. This is not a guarantee, but it gives you a written letter confirming the maximum loan amount based on your income, debts, and the bank's current internal affordability test. The HKMA's regulatory framework sets the floor; banks set the ceiling.
For the current DSR limit (50%) and LTV rules (70%), refer to the HKMA residential mortgage guidelines issued on 16 October 2024. Confirm with your bank that they have adopted these terms, as individual banks may have tighter policies for certain property types or borrower profiles.