Bart De Wever's 'supernote' proposes additional taxation on properties, which is set to impact a significant number of landlords across Belgium.

In a related move, the Flemish Socialists have introduced a marginal tax rate on rental income, potentially leading to substantial tax increases for landlords with multiple properties.

These proposed changes are likely to benefit single-property landlords while significantly increasing the tax burden for those owning multiple properties, with some facing a potential doubling of their tax obligations.

According to BNP Paribas, the latest adjustments to the taxable base for real estate income will affect over 600,000 landlords.

Meanwhile, the Flemish Christian Democrats are advocating for a radical overhaul by proposing a flat 25% tax on all rental income, moving away from the current system based on cadastral income.

Initial proposals included a tax increase specifically targeting third properties, but this condition was ultimately removed following pushback from the Francophone Liberals.

To safeguard small investors, suggestions have been made to include a 30% deduction on expenses and an exemption for the first 6,000 euros of rental income.

Currently, a property with a cadastral income of 500 euros rented for 900 euros incurs approximately 760 euros in annual tax, which reflects a 7% rate that would rise significantly under the new proposals.