Nueva impuesto del 10% sobre las ganancias de capital de Bélgica y su impacto en el comportamiento de los inversores

Belgium's impending 10% capital gains tax on financial assets, set to take effect on January 1, 2026, represents a seismic shift in the country's tax landscape. This reform, which targets individuals and non-commercial entities while exempting commercial companies, introduces a complex framework of exemptions, carry-forward rules, and differential tax rates. For investors, the implications are profound, necessitating a reevaluation of portfolio structures, timing of transactions, and asset allocation strategies.

The Mechanics of the New Tax

The tax applies to capital gains realized on or after January 1, 2026, with historical gains grandfathered and exempt. The calculation of taxable gains hinges on a "snapshot value" of assets as of December 31, 2025. For example, if an asset's purchase price is lower than its value on that date, the latter becomes the deemed cost basis for future gains. This creates a critical incentive for investors to crystallize gains before the end of 2025 to avoid the new tax regime.

An annual exemption of €10,000 per taxpayer, indexed for inflation, is available, with unused portions carryable forward for up to five years, capped at €15,000 per individual (€30,000 for couples) for jointly held assets according to the tax authority. However, capital losses can only offset gains in the same year and asset category, with no carry-forward permitted as reported by KBC. For significant shareholders (holding 20% or more in a company), a separate regime applies: the first €1 million of gains over five years is exempt, followed by progressive rates from 1.25% to 10% as detailed in Mondaq.

Strategic Tax Planning: Timing and Exemptions

Investors must now prioritize timing their transactions to maximize exemptions and minimize exposure. For instance, selling assets with substantial unrealized gains before December 31, 2025, could lock in lower historical cost bases, shielding future appreciation from the 10% tax. Conversely, holding onto assets with losses until 2026 allows for tax-efficient harvesting, as losses can offset gains in the same year according to Baker Tilly.

The carry-forward exemption also demands careful planning. Investors with gains below the €10,000 threshold in 2026 may strategically defer sales to subsequent years to utilize unused exemptions, particularly if inflation indexing increases the annual limit as noted by PwC. However, the five-year cap means that aggressive deferral could lead to unutilized exemptions, necessitating a balance between immediate and future tax efficiency.

Asset Reallocation: Shifting Toward Exempt and Low-Tax Assets

The tax's scope-covering shares, cryptocurrencies, bonds, and foreign currencies but excluding real estate, artworks, and certain insurance products-creates a clear incentive to reallocate portfolios toward exempt or low-tax assets. For example, investors may shift from equity-heavy portfolios to real estate or collectibles, which remain outside the tax's purview. Similarly, life insurance policies and pension savings, explicitly excluded from the tax, could become more attractive for capital preservation.

For substantial shareholders, the 33% tax rate on "internal transfers" (e.g., selling shares to a controlled company) introduces a disincentive for such transactions. Instead, investors may explore alternative structures, such as gifting shares or restructuring ownership to avoid triggering the higher rate.

Institutional and Cross-Border Considerations

Financial institutions face operational challenges, including updating IT systems to track asset valuations as of December 31, 2025, and automating tax calculations. For cross-border investors, the "exit tax" on individuals relocating abroad-taxing gains if assets are sold within two years of departure-adds another layer of complexity. This could influence relocation strategies, particularly for high-net-worth individuals with significant Belgian-held assets.

Conclusion: Adapting to a New Tax Reality

Belgium's 10% capital gains tax is not merely a revenue measure but a catalyst for structural changes in investor behavior. Strategic tax planning will center on timing, exemption optimization, and asset reallocation, while institutions must adapt to new compliance demands. As the implementation date approaches, investors who proactively adjust their strategies will be best positioned to navigate this evolving landscape.