What is borrowing capacity and why does it matter?
Your borrowing capacity is the maximum amount a Belgian bank agrees to lend you to finance a property purchase. It depends on three things: your income, your charges, and your personal down payment. As simple — and as tricky — as that.
Why is it crucial to calculate it before visiting? Because falling in love with a property you can't afford is the best way to waste 3 months of searching. And because the bank won't cut you any slack: it applies strict rules, recommended by the National Bank of Belgium (NBB) and applied by all Febelfin members.
Before going further, keep in mind that on top of your monthly mortgage payment come the purchase costs (registration duties, notary, VAT if new-build) which are almost never financed by the bank. That's cash you need to have in your account on the day of the deed.
The one-third rule — the famous 33% explained
The golden rule of Belgian banks is simple: your monthly mortgage payment cannot exceed one third of your monthly net income. This is what we call the debt ratio.
Debt ratio = (mortgage payment + other fixed charges) ÷ monthly net income
This ratio must stay at or below 33%. Beyond that, the bank considers you at risk of running into financial trouble.
Example: if you earn EUR 2,500 net per month, your maximum monthly payment will be around EUR 825. At a rate of 3.3% over 25 years, that corresponds to a loan of about EUR 170,000.
Some banks accept going up to 38-40% for strong files: high income, large down payment, long-standing permanent contract, no other credits. But that's the exception. The majority of mortgage refusals come from this very ratio.
Which income does the bank take into account?
Not all your income is treated equally by the banker. Here's what really counts, and what gets dropped.
| Type of income | Counted? | How |
|---|---|---|
| Net permanent-contract salary | ✅ Yes | 100% of monthly net |
| 13th month & double holiday pay | ✅ Yes | Divided by 12, added to monthly net |
| Variable bonuses & premiums | ⚠️ Partly | 50% to 80% depending on stability (3-year history) |
| Meal vouchers, eco-vouchers | ❌ No | Treated as benefits, not income |
| Rental income | ⚠️ 70-80% | Discount for vacancy and maintenance |
| Family allowances | ⚠️ Variable | Often counted if young children |
| Self-employed income | ✅ Yes | Average net of the last 3 accounting years |
| Alimony received | ⚠️ Sometimes | If written ruling and stable |
| Unemployment benefit | ❌ No | Considered unstable income |
If you're not sure of your actual net income, run the check: our Belgian net salary calculator gives you the exact figure, and our guide to understanding your Belgian payslip breaks down every line — handy when the banker asks for your last three pay slips.
The charges that drag your file down
On the other side of the equation, the bank adds up all your fixed monthly charges. They are deducted from your capacity before it even calculates the mortgage payment.
Beyond the debt ratio, the bank also checks that you have enough left to live on after paying your monthly payment. Generally, we're talking about a minimum of EUR 1,000 per adult + EUR 250 per dependent child. If your file passes the 33% but fails the "living balance", it can still get blocked.
The down payment — what's the minimum in 2026?
Since the NBB's reinforced recommendations, the days when you could borrow 100% of the purchase price with nothing down are over. Today, almost every bank requires a down payment.
Concretely, for a flat at EUR 280,000 in Brussels, your minimum down payment is made up of two parts:
| Item | Estimated amount | Detail |
|---|---|---|
| 10% of price (own funds) | EUR 28,000 | If 90% LTV |
| Registration duties (Brussels with abatement) | EUR 10,000 | 12.5% × (280,000 − 200,000) |
| Notary fees & mortgage registration | ~EUR 6,500 | Fees + disbursements + mortgage |
| Total down payment needed | ~EUR 44,500 (about 16% of the price) | |
The exact rates vary by region: 12.5% in Brussels with abatement, 3% in Wallonia for own and unique residence, and 2% in Flanders. That radically changes the down payment required.
If you're actively saving for a purchase in 12-24 months, don't leave your money sitting in a 0.5% account. Belgian government bonds 2026 or a term savings account can yield between 2% and 3% net over a short horizon, with no risk. For longer-term savings, also see our guide on pension savings.
Worked examples — how much can you really borrow?
Time for the numbers. Here are three typical 2026 profiles, with an indicative fixed rate of 3.3% over 25 years and a strict one-third rule.
| Profile | Net income | Charges | Max monthly payment | Estimated capacity |
|---|---|---|---|---|
| Single, permanent contract | EUR 2,200 | EUR 0 | EUR 726 | ~EUR 150,000 |
| Single, permanent contract | EUR 2,800 | EUR 250 (car) | EUR 674 | ~EUR 140,000 |
| Couple, permanent contract, no kids | EUR 4,000 | EUR 0 | EUR 1,320 | ~EUR 270,000 |
| Couple, permanent contract + 1 child | EUR 4,500 | EUR 400 (car + lease) | EUR 1,085 | ~EUR 225,000 |
| Couple, high earners | EUR 6,500 | EUR 0 | EUR 2,145 | ~EUR 440,000 |
These numbers are indicative. Each bank has its own scorecard, and a broker can get you +5 to +15% extra capacity depending on your profile.
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Extra criteria banks look at in 2026
The debt ratio isn't the only factor. Here are all the other criteria put under the microscope.
How to boost your borrowing capacity
Your current capacity isn't enough for your project? Here are the concrete levers that actually work.
Increasing your down payment by EUR 10,000 on a EUR 250,000 loan over 25 years is roughly EUR 50 less per month. Nothing to sneeze at when you're at the 33% limit.
Source: Febelfin and Belgian bank simulatorsCommon mistakes that wreck the calculation
Here are the pitfalls I see come up most often — better to avoid them before you submit your file.
- Forgetting purchase costs in your budget — 12 to 17% of the price depending on the region, payable in cash. Check via our complete guide to registration duties.
- Not including the outstanding-balance insurance cost in the 33% calculation — it can tip the file.
- Confusing gross and net income — the bank only counts the net.
- Running a recurring overdraft before applying — clean up your spending habits 3 to 6 months ahead.
- Underestimating fixed charges — subscriptions, leases, school: the bank reviews everything over 3 months.
- Asking for 100% without doing your homework — better a tight file at 85% than a refusal at 100%.
And if you're also considering a rental investment rather than a main residence, run the numbers first in our property investment ROI calculator — borrowing capacity is treated differently there (future rental income is partly taken into account).
Wrap-up — the key takeaways
- Belgian borrowing capacity is capped by the one-third rule: max monthly payment = 33% of monthly net.
- The 13th month and double holiday pay are included; meal vouchers are not.
- All your other credit monthly payments (car, lease, consumer) are deducted before calculation.
- Minimum down payment: 10-15% of the price + purchase costs out of your own pocket.
- The maximum LTV is 90% for the main residence, 80% for investment.
- The loan must be repaid before age 70-75 depending on the bank.
- Once your capacity is validated, get ready for the signing of the sale agreement: that's where you really commit.
- All figures here are indicative. For your specific case, consult your bank or a credit broker.