Taxation depends on the type of lease
For residential leases, the landlord is taxed on the indexed cadastral income (CI) + 40%, not on actual rental income. Only mortgage interest is deductible. For professional-use leases, the actual rent is taxed and the landlord can deduct a lump-sum expense allowance (40% of gross rent, capped at 2/3 of the revalued CI).
Belgium’s tax system for rental income is relatively favourable for residential landlords because taxation is based on the cadastral income (a notional income based on the property’s cadastral value) rather than actual rent received. This usually results in a lower tax base than the actual rental income.
Residential vs professional lease
| Aspect | Residential lease | Professional lease |
|---|---|---|
| Tax base | Indexed CI + 40% | Actual rent received |
| Expense deduction | Only mortgage interest | Lump-sum (40% of gross rent) |
| Deduction cap | No cap on mortgage interest | 2/3 of revalued CI x 3.47 |
| Property tax (precompte immobilier) | Not deductible from income | Not deductible from income |
| Net result | Usually lower tax | Usually higher tax |
The distinction matters significantly: if your tenant uses the property for professional purposes (and declares the rent as a business expense), the tax authorities will tax you on the actual rent rather than the cadastral income.
If the lease does not specify the split between private and professional use, the tax authorities may treat the entire rent as professional income. Always include a clear split in the lease when the property is used partly for professional purposes.
Deductible expenses in detail
Mortgage interest
Mortgage interest on the loan used to purchase the rental property is deductible from all categories of rental income. This is the most significant deduction available to residential landlords.
Property tax (precompte immobilier)
The property tax is not directly deductible from rental income for tax purposes, but it reduces the landlord’s overall cost base.
Maintenance and repairs
For professional leases where actual income is taxed, maintenance and repair costs are covered by the lump-sum deduction (40% of gross rent). The landlord does not need to justify individual expenses.
Insurance
Building insurance premiums are not separately deductible for residential leases (covered by the CI-based taxation) but are included in the lump-sum for professional leases.
Management fees
Fees paid to a property management company are not separately deductible for residential leases but are covered by the lump-sum for professional leases.
BailBelgique provides landlords with tools to track rental income, expenses and tax obligations for each property.
Regional specifics
Rental income taxation is a federal matter in Belgium. The tax rules described above apply uniformly across Brussels, Wallonia and Flanders.
However, the property tax (precompte immobilier / onroerende voorheffing) varies by region:
- Brussels: base rate of 2.25% of the CI
- Wallonia: base rate of 1.25% of the CI
- Flanders: base rate of 3.97% of the CI (Flemish discount may apply)
These rates are multiplied by municipal centimes (additionnels) which vary by municipality.
Belgian Income Tax Code 1992, Art. 7-13 — Rental income taxation rules for residential and professional leases.