Guide to Mortgages in Belgium

Mortgages in Belgium: The Basics

The mortgage is the cornerstone of property ownership in Belgium. In 2025, approximately 85% of property purchases are partly financed by a mortgage. Understanding how it works, its subtleties, and Belgium-specific rules is essential for securing the best conditions and avoiding pitfalls.

Unlike other European countries, the Belgian mortgage market is dominated by major banks (BNP Paribas Fortis, KBC, ING, Belfius) which hold approximately 70% of the market. This relative concentration still leaves room for negotiation, especially if you present a strong profile.

Fixed vs Variable Rate: Which to Choose?

Fixed Rate

The fixed rate is the most common choice in Belgium (approximately 80% of mortgages). Your monthly payment remains the same throughout the loan term, offering total budgetary certainty.

• Average rate February 2025: 3.1 to 3.5% over 20 years, 3.2 to 3.6% over 25 years
• Advantage: total predictability, protection against future increases
• Disadvantage: higher initial rate than variable, no benefit if rates fall

Variable Rate

The variable (or revisable) rate is indexed to a reference rate and adjusted periodically. In Belgium, the most common formulas are:

• 1/1/1: annual revision (most risky)
• 3/3/3: revision every 3 years
• 5/5/5: revision every 5 years (most popular variable)
• 10/5/5: fixed for 10 years, then revisable every 5 years

Belgian legal protection: the law limits the variable rate increase to double the initial rate. If your starting rate is 2.5%, it can never exceed 5%. This protection is unique in Europe and makes variable rates less risky than elsewhere.

Average Variable Rate in 2025

• 5/5/5 over 20 years: 2.7 to 3.1%
• 10/5/5 over 25 years: 3.0 to 3.3%

The gap between fixed and variable is relatively small in 2025 (0.3 to 0.5 percentage points). In this context, the fixed rate is generally recommended unless you are certain of selling before the first revision.

National Bank of Belgium (NBB) Rules

Since 2020, the NBB imposes prudential rules on banks to limit over-indebtedness:

Loan-to-Value (LTV)

• Own residence (first purchase): maximum 90% of the property price. You must contribute at least 10% plus acquisition costs (notary, registration fees). In practice, budget 20 to 25% of the total price.
• Own residence (non-first purchase): maximum 90%
• Buy-to-let investment: maximum 80%. You must therefore contribute at least 20% plus costs.

The NBB does allow banks to exceed these limits for 35% of first-time buyer applications (of which 5% can go up to 100%). This means a 100% mortgage remains possible, but is reserved for the strongest applications.

Debt-Service-to-Income Ratio (DSTI)

Monthly payments on all your loans must not exceed one third of your net income. For a couple earning 5,000 euros net per month, the maximum monthly payment is therefore 1,667 euros.

Outstanding Balance Insurance

Outstanding balance insurance (ASRD/SSV) is quasi-mandatory in Belgium: banks require it in 95% of cases. It repays the remaining capital in the event of the borrower's death.

Cost of the Insurance

The cost depends on your age, health, and insured capital:

• 30-year-old borrower, non-smoker: approximately 0.08% of capital per year, i.e. approximately 200 euros/year for 250,000 euros
• 40-year-old borrower, non-smoker: approximately 0.15%, i.e. 375 euros/year
• 50-year-old borrower: approximately 0.30%, i.e. 750 euros/year

Tax Advantage

Insurance premiums qualify for a 30% tax reduction at federal level (long-term savings tax regime). For an annual ceiling of 2,450 euros in premiums, the tax saving can reach 735 euros per year.

How to Get the Best Rate

Prepare Your Application

• High personal contribution: the lower your LTV, the better the rate. A contribution of 20% or more gives access to the best rates.
• Professional stability: a long-standing permanent contract is ideal. Self-employed must present at least 3 years of positive accounts.
• No outstanding debts: repay consumer loans before applying for a mortgage.
• Good banking history: no recurring overdrafts, no listing with the NBB Credit Register.

Negotiate Actively

• Approach at least 3 banks: rates vary by 0.2 to 0.5 percentage points between banks for the same application.
• Play the competition: show competing offers to get a counter-proposal.
• Negotiate application fees too: banks can reduce or waive them (500 to 1,000 euros saved).
• Use a broker: mortgage brokers (free for you, paid by the bank) have access to the entire market and can obtain preferential conditions.

Loan Duration: What Impact?

For a 250,000-euro loan at a fixed rate of 3.3%:

• 20 years: monthly payment 1,428 euros, total interest cost: 92,720 euros
• 25 years: monthly payment 1,220 euros, total interest cost: 116,000 euros
• 30 years: monthly payment 1,096 euros, total interest cost: 144,560 euros

Extending from 20 to 25 years reduces the monthly payment by 208 euros but costs an extra 23,280 euros in interest. The choice depends on your monthly budget and goals. Simulate your mortgage with our mortgage simulator.

Early Repayment

In Belgium, you can repay your mortgage early, but the bank may charge a reinvestment indemnity (penalty) legally capped at 3 months' interest on the capital repaid early. For a remaining capital of 200,000 euros at 3.3%, this represents approximately 1,650 euros.

Checklist Before Signing

• Compare at least 3 mortgage offers (APR, not just the nominal rate)
• Check outstanding balance insurance costs (compare outside the bank too)
• Understand the variable rate conditions if choosing one
• Check application and valuation fees
• Calculate your TOTAL monthly budget (mortgage + insurance + property tax + charges)
• Budget a safety margin of 10 to 15%
• See our notary fees guide for a complete estimate of acquisition costs