When a buyer asks, “How much mortgage can this income support?”, the answer starts with monthly repayment capacity, not the apartment price. In a Korean housing context, DSR is one of the key ways to frame that repayment capacity.
This article uses a simple user-entered DSR 40% example with a 4.0% annual rate, 30-year equal-payment mortgage, and no existing debt. To test your own cash, LTV, existing debt, and target home price, open the DSR/LTV Calculator.
After the calculator gives you a safer search range, compare that range with transaction prices in the Real Estate Dashboard. The numbers below are simulations, not Korean policy automation or lender approvals.
Quick Summary
- In this example, DSR 40% means annual debt payments are limited to 40% of annual income.
- KRW 60 million of annual income gives about KRW 2 million of monthly payment capacity.
- At 4.0% over 30 years, that payment supports about KRW 418.92 million of mortgage principal.
- Existing monthly debt payments reduce the room available for a new mortgage.
- Passing DSR does not guarantee that LTV, cash, transaction costs, or lender review will pass.
- Use the DSR/LTV Calculator, then check the safer KRW price band in the Real Estate Dashboard.
Assumptions
| Item | Input |
|---|---|
| DSR | 40% |
| Existing debt | KRW 0 |
| Interest rate | 4.0% per year |
| Loan term | 30 years |
| Repayment method | Equal monthly principal-and-interest payment |
| Excluded from table | LTV, cash on hand, closing costs, credit review, collateral valuation |
The FinMap calculator does not automatically apply Korean mortgage policy updates. It uses the DSR and LTV values you enter and calculates an equal-payment loan.
DSR 40% Loan Capacity by Annual Income
| Annual income | Annual payment capacity | Monthly payment capacity | Estimated loan capacity |
|---|---|---|---|
| KRW 30M | KRW 12.00M | KRW 1.00M | KRW 209.46M |
| KRW 40M | KRW 16.00M | KRW 1.33M | KRW 279.28M |
| KRW 50M | KRW 20.00M | KRW 1.67M | KRW 349.10M |
| KRW 60M | KRW 24.00M | KRW 2.00M | KRW 418.92M |
| KRW 70M | KRW 28.00M | KRW 2.33M | KRW 488.74M |
| KRW 80M | KRW 32.00M | KRW 2.67M | KRW 558.56M |
| KRW 100M | KRW 40.00M | KRW 3.33M | KRW 698.20M |
| KRW 120M | KRW 48.00M | KRW 4.00M | KRW 837.84M |
This is the DSR side only. Actual apartment affordability also depends on LTV, available cash, closing costs, and property-specific underwriting.
What Existing Debt Does
Using KRW 60 million of annual income, DSR 40%, 4.0% rate, and a 30-year term:
| Existing monthly debt | New mortgage payment room | Estimated new mortgage capacity |
|---|---|---|
| KRW 0 | KRW 2.00M | KRW 418.92M |
| KRW 0.50M | KRW 1.50M | KRW 314.19M |
| KRW 1.00M | KRW 1.00M | KRW 209.46M |
| KRW 1.50M | KRW 0.50M | KRW 104.73M |
The key point is simple: existing debt consumes DSR room. Credit loans, auto loans, student loans, and other amortizing obligations can all reduce the room for a new Korean mortgage.
Example: KRW 60M Income and KRW 200M Cash
| Item | Result |
|---|---|
| Annual income | KRW 60M |
| Cash on hand | KRW 200M |
| DSR / LTV inputs | 40% / 70% |
| Rate / term | 4.0% / 30 years |
| DSR-based loan capacity | KRW 418.92M |
| LTV/cash price limit | KRW 571.43M |
| Safer search range | KRW 457.14M ~ KRW 514.29M |
In this example, cash, LTV, and closing costs bind before income-based repayment capacity. You can take this safer range to the Real Estate Dashboard and see where actual Seoul, Gyeonggi, and Incheon transactions cluster.
Misunderstanding Box: DSR Capacity Is Not the Home Price
Misunderstanding: “If DSR supports about KRW 419M of loan principal, a KRW 600M home should be fine.”
Not necessarily. With a KRW 600M target home, 70% LTV, and 5% transaction-cost assumption, the required cash is about KRW 210M. If the buyer has KRW 200M, the cash check is short even before lender-specific review.
Use the DSR/LTV Calculator target home field to check DSR, LTV, and cash separately.
Checklist Before Applying the Table
- Confirm whether the income amount is the income a lender may recognize.
- Add all existing monthly debt payments.
- Enter the DSR and LTV values yourself; do not treat this article as policy automation.
- Separate cash you can use from cash you want to keep as a reserve.
- Include a closing-cost assumption.
- Compare the calculator’s safer search range with actual prices in the Real Estate Dashboard.
Related Reading
- How Much Does a 1pp Rate Move Reduce Mortgage Capacity?
- Mortgage Risk Checklist Before Buying an Apartment
- Why Passing DSR May Still Not Be Enough
Bottom Line
The income table is a starting point. Real apartment affordability needs DSR, LTV, available cash, closing costs, and existing debt in the same view.
Use the DSR/LTV Calculator for your own assumptions, then open the Real Estate Dashboard to compare your safer search range with real KRW transaction prices.
FAQ
Is DSR 40% a live Korean policy setting?
This article uses 40% as an example input. FinMap does not automatically apply policy updates. Enter the DSR and LTV assumptions you want to test.
Is the table a bank approval schedule?
No. It is a simulation using a 4.0% rate, 30-year equal-payment loan, and no existing debt. Lender review can differ.
How should I enter existing debt?
Add the monthly repayment amounts for existing loans and enter them as existing monthly debt payments in the calculator.
Which matters more, DSR or LTV?
Both matter. DSR tests income-based repayment capacity; LTV tests loan size relative to property value. Cash and transaction costs can be equally binding.
What is the safer search range?
It is 80-90% of the estimated maximum affordable purchase price. It is meant as a conservative range before checking real transactions.