Brazil's Federal Revenue Service has opened a public consultation from 6 November on proposed changes to the Additional CSLL regulation, which would bring parts of the OECD's Side-by-Side Package into domestic rules from 1 January 2027.
Brazil’s Federal Revenue Service (RFB) opened a public consultation on 6 November 2026 on amendments to Normative Instruction RFB No. 2.228 of 3 October 2024, which regulates the Additional Social Contribution on Net Profit (CSLL).
The Additional CSLL was introduced by Provisional Measure No. 1.262 of 3 October 2024 and Law No. 15.079 of 27 December 2024. It is part of Brazil’s adaptation to the Global Anti-Base Erosion Rules (GloBE Rules) under Pillar Two, and allows Brazil to collect the Top-up Tax owed by in-scope Multinational Enterprise Groups that are lightly taxed in the country.
Why the rules are being updated
The Receita Federal said the regulation must be revised periodically to reflect new Reference Documents published after 31 December 2023. This is so that the Additional CSLL continues to be treated as a Qualified Domestic Minimum Top-up Tax (QDMTT).
The proposal would incorporate part of the Agreed Administrative Guidance approved by the OECD Inclusive Framework in January 2026. It focuses mainly on the Simplified ETR Safe Harbour (SESH) in Chapter 02 of the Side-by-Side Package.
Changes to IN RFB No. 2.228
A new Single Annex would implement the GloBE Simplified Effective Tax Rate Rule (RSGAE). It covers the Simplified Test and the definition of Tested Jurisdiction, along with Jurisdictional Profit or Loss Before Income Tax (JLAT) and Jurisdictional Taxes on Income or Profit (JTRL) and their respective adjustments. Transition rules, the allocation of profits, losses and taxes between Constituent Entities, Tax Transparent Entities, and eligibility restrictions and integrity rules for the RSGAE are also addressed.
Changes to IN RFB No. 1.520
The consultation also covers Normative Instruction RFB No. 1.520 of 4 December 2014. New Articles 11-A, 30-A, 30-B and 30-C would govern the deduction by legal entities domiciled in Brazil of income tax paid abroad by controlled or affiliated companies. This applies where the foreign tax arises from a domestic minimum tax regime, tax consolidation, group taxation or tax transparency. The articles would also clarify how crediting of tax paid abroad works in such cases.
How to take part
Companies, academia and other interested parties may send submissions, preferably as a PDF file, to [email protected]. Participants are asked to state whether they agree with the proposed changes, flag any other Administrative Guidance issues published up to January 2026 that need attention in IN RFB No. 2.228, and suggest wording improvements. They may also request that their identification or personal data be removed if the submissions are published.
The Receita Federal said it aims to strengthen legal certainty in transposing the rules into domestic law while protecting the national tax base.
The consultation will remain open until 16 November 2026.
