In Belgium
The deductibility of property expenses in Belgium depends primarily on whether the property is let to an individual for private use or to a company/for professional use.
Private letting (most common case). When a property is let to an individual for private use, the owner declares the indexed cadastral income increased by 40%. A flat-rate deduction is already built into the CI calculation — the owner cannot deduct actual expenses on top.
Professional letting. When a property is let for professional use (to a company or self-employed person), the owner declares the actual rent received. In this case, actual expenses can be deducted, including maintenance, repairs, insurance premiums and depreciation.
Mortgage interest. Interest on a mortgage for the purchase, construction or renovation of a property remains deductible under certain conditions, regardless of the type of letting.
Practical example
Pierre owns two apartments. Apartment A is let to a family (private use): he declares the indexed CI + 40% and cannot deduct his 2,000 EUR roof repair. Apartment B is let to a law firm (professional use): he declares the actual rent of 14,400 EUR/year and deducts the repair, insurance and depreciation, reducing his taxable rental income significantly.