The Ultimate Guide to DSR, LTV, and DTI: How Much Mortgage Can You Get on Your Salary?

I still remember the day I went to get my mortgage approved after signing the contract for my first home. I mindlessly signed my name dozens of times on stacks of financial documents without really understanding what it all meant. Even though I was buying a home worth hundreds of millions of won, faced with unfamiliar legal and financial terms, I just nodded, assuming they would take care of it properly.

Today, mortgage regulations have become much tighter. It's now essential to carefully calculate your maximum limit before you even start looking for a home. But combinations of letters like LTV, DTI, and DSR still feel foreign and difficult.
To help you protect your precious assets and confidently prepare for buying your first home, let's clearly break down these key terms from a beginner's perspective.

💡 If you want to check the safety of a property before calculating your loan limit, read our guide on How to Read the Warning Signs in a Korean Property Register first.

1. Core Mortgage Concepts at a Glance

The three main metrics that determine your loan limit are divided into "home price-based" and "income-based" criteria.

• LTV (Loan to Value ratio): A home price-based ratio that asks, "What percentage of the home's price will they lend me?"
• DTI (Debt to Income ratio): The first income-based ratio that asks, "What percentage of my annual income goes toward the principal and interest of my mortgage, plus the interest on other loans?"
• DSR (Debt Service Ratio): The strictest final income-based regulation that asks, "What percentage of my annual income goes toward the 'principal + interest' of all my loans, including mortgages, credit loans, and car financing?"

2. LTV Limits by Regulated Zones and Housing Types

LTV is the maximum amount you can borrow relative to the home's price (based on KB market price or appraisal value). For example, if a 60% LTV is applied to an apartment worth 500 million KRW (~$375,000 USD), your maximum loan limit based on the home's price is 300 million KRW (~$225,000 USD).

💡 The "home price" here is often based on the bank's KB Price, not the actual transaction price, which can make your loan limit feel different from what the sale price suggests. See KB Price vs. Actual Transaction Price: Why Is Only My Loan Coming Up Short? for the details.

⚠️ Warning for Multi-Home Owners

For those owning two or more homes in the capital region and regulated areas, a 0% LTV applies, meaning you cannot receive a single penny in mortgage loans for purchasing a home. Furthermore, under recent tightened household debt policies, extending the maturity of existing mortgages for multi-home owners is generally prohibited, requiring careful financial management.

3. DTI vs DSR: Income-Based Regulations Monitoring Your Wallet

While both DTI and DSR calculate your loan limit based on your annual salary (income), there is a crucial difference in how they factor in "other loans."

DTI and DSR Formula Comparison

$\text{DTI} = \frac{\text{Mortgage (Principal + Interest)} + \text{Other Loans (Interest Only)}}{\text{Annual Total Income}} \times 100$

$\text{DSR} = \frac{\text{Mortgage (Principal + Interest)} + \text{Other Loans (Total Principal + Interest)}}{\text{Annual Total Income}} \times 100$

A strict DSR limit of 40% applies to borrowers whose total bank debt exceeds 100 million KRW (~$75,000 USD). In other words, the sum of all principal and interest you must repay in a year cannot exceed 40% of your annual salary.

4. Practical Examples: Simulated Loan Limits by Salary

Here are estimated maximum loan limits based on a 40% DSR, a 4.0% annual mortgage rate, and a 40-year maturity with equal principal and interest installments (assuming a debt-free state with no other existing loans).

Salary 40 million KRW vs 60 million KRW Limit Comparison

• Salary of 40 million KRW (~$30,000 USD):
  • Annual principal and interest limit (40% DSR): **16 million KRW (~$12,000 USD)** (about 1.33 million KRW / ~$1,000 USD per month)
  • Estimated max loan amount: Around 310 million KRW (~$232,500 USD)
• Salary of 60 million KRW (~$45,000 USD):
  • Annual principal and interest limit (40% DSR): **24 million KRW (~$18,000 USD)** (2 million KRW / ~$1,500 USD per month)
  • Estimated max loan amount: Around 470 million KRW (~$352,500 USD)

Note: If you have credit loans, an overdraft account (minus account), or car installments, the principal and interest for these already take up some of your DSR limit, drastically reducing your mortgage limit.

5. 3 Practical Tax and Financial Strategies to Increase Your Loan Limit

1. Pay off unnecessary credit loans and overdraft accounts in advance: Even for small amounts, credit loans have short maturities when calculating DSR, heavily eating away at your limit. It's beneficial to close or repay your overdraft accounts before applying for a mortgage.
2. Extend your loan maturity: By extending the loan term from 30 years to 40 years (or 50 years if conditions are met), the annual principal and interest burden decreases, allowing you to borrow more money within the DSR limit.
3. Utilize government policy financial products: Government products like the Didimdol (Stepping Stone) Loan or Buteemmok (Support) Loan offer lower interest rates than standard commercial bank loans and feature relaxed DSR conditions, so they should be considered first.

6. Frequently Asked Questions (FAQ)

Q1. Is it possible for freelancers or unemployed people to calculate their DSR?

Yes, it is possible. However, freelancers must pay special attention to the income recognition method.

When I applied for a loan as a freelancer, due to expense deductions from my total revenue, I faced a situation where only about 50% of my actual income was officially recognized. Because my solo income alone drastically fell short of my originally planned mortgage limit, I was in a massive panic right up until the loan was executed.

Ultimately, I was only able to hit my target loan amount by combining my spouse's income and re-applying with our joint income. If you are a freelancer or self-employed, there can be a significant gap between what you consider your actual revenue and the income the bank recognizes. Therefore, I highly recommend checking closely with your branch beforehand to see if you can utilize a "joint spousal income" or "estimated income" based on your National Health Insurance premiums.

Q2. Can I increase my loan limit by combining my income with my spouse's?

Yes, you can apply joint spousal income when applying for a mortgage. However, keep in mind that if you use joint income, your spouse's existing loans (credit loans, installments, etc.) will also be subject to the DSR assessment, so careful advance review is necessary.

Q3. Will my loan limit decrease if the stress DSR is applied?

Yes, it will. The stress DSR is a system that calculates your DSR by adding an extra spread (stress rate) to the actual interest rate, accounting for future interest rate fluctuation risks. Therefore, even with the exact same salary, if the stress DSR is applied, the borrower's loan limit will slightly decrease compared to before.