Most of the measures announced by the 2017 Belgian summer agreement were finally adopted in the Law of 25 December 2017 on the reform of corporation income tax (as published in the Belgian Gazette on 29 December 2017).
According to the explanatory memorandum of the draft law, the government's objective was "to aim for a simplified system with a higher level of fairness and legal certainty".
This reform, which aims to be budget neutral, focuses on two main elements: the lowering of the nominal corporate tax rate and the broadening of the tax base.
The law of 25 December 2017 was also an opportunity for the government to transpose into Belgian law the tax rules adopted within the ATAD Directive I & II.
The reform comes into force in three phases.
The first new measures (Phase I) entered into force on 1 January 2018 and are applicable as from tax year 2019 relating to a taxable period which begins at the earliest on 1 January 2018 at least.
Other measures (Phase II) will enter into force on 1 January 2019 and will be applicable as from tax year 2020 relating to a taxable period which begins at the earliest on 1 January 2019. These measures include introducing a limited tax consolidation.
Finally, the last measures (Phase III) are planned to enter into force on 1 January 2020 and will be applicable as from tax year 2021 for a taxable period which begins at the earliest on 1 January 2020.