Exemption or Reduction of Property Tax

Exemption or Reduction of Property Tax (Immovable Property Tax): First Deadline 31 March 2026 (Flanders/Wallonia/Brussels-Capital Region)
 

For owners of real estate located in the Flemish Region, the Walloon Region or the Brussels-Capital Region, property tax may, in certain situations, be fully or partially reduced.

Where a building was vacant in 2025, generated no income, was destroyed, or remained out of use for an extended period, it is advisable to assess in a timely manner whether an exemption or proportional reduction can be claimed.
 

1. PROPORTIONAL REDUCTION IN CASE OF INVOLUNTARY UNPRODUCTIVITY

A proportional reduction may be granted in the Flemish Region and the Walloon Region where:

• the property concerns a built and, in principle, unfurnished immovable property;
• the property was unproductive for at least 90 days (Flemish Region) or 180 days (Walloon Region) during 2025, not necessarily consecutively;
• the building was completely unused and unproductive during the relevant period, both conditions being cumulative;
• no income was effectively generated;
• the involuntary unproductivity can be sufficiently substantiated, for example through utility consumption data, rental or sale listings, renovation invoices, court documents, soil investigations, etc.
   

For immovable property located in the Brussels-Capital Region, no reduction of property tax is available on the grounds of unproductivity.
 

2. EXEMPTION OR REDUCTION IN CASE OF DESTRUCTION

In the Flemish Region/ Walloon Region, a proportional reduction may also be obtained in the event of the total or partial destruction of a building, notably where:

• the destroyed portion represents at least 25% of the cadastral income;
• the destruction results from a disaster (e.g. fire or collapse).
   

3. UNPRODUCTIVITY OF MACHINERY AND EQUIPMENT

For companies, a proportional reduction may also be available for machinery and equipment (certain equipment, machinery and other installations – immovable by nature or by destination) that were wholly or partially out of operation (at least 25%) for a minimum period of 90 days in 2025 (not necessarily involuntary).

In the Walloon Region, investments made between 1 January 2021 and 31 December 2025 are exempt for a maximum period of five assessment years. Please refer to our previous Tax Insight in this regard.

In the Brussels-Capital Region, property tax is no longer due to machinery and equipment.
 

TAKE ACTION IN GOOD TIME BEFORE 31 MARCH 2026 (SPECIFICALLY FOR FLEMISH REGION)

The reduction or exemption is not granted automatically and must be claimed each year.

An objection must be filed against the assessment notice with the Flemish Tax Administration. For assessment year 2025, the deadline is in principle 31 March 2026.

If the assessment notice is received in 2026, the standard objection period of three months applies.

For immovable property located in the Walloon Region, a request for reduction must be submitted to the Walloon tax authorities within six months following the date of issuance of the assessment notice.
 

HOW CAN WE ASSIST YOU?

RSM can assist affected companies, inter alia, with:

• identifying potential reductions or exemptions to which your company may be entitled;
• supporting companies in their communications and procedures with the competent tax authorities;
• assisting with the preparation of your formal objection.
   

For any questions regarding the above matters, please do not hesitate to contact the RSM Belgium Tax team via tax@rsmbelgium.be.
 

RSM Belgium | Tax