Under Version 1.40 of Technical Note 2025.002-RTC (May 20, 2026), Brazil will require all NF-e documents to include the IBS and CBS tax group starting August 3, 2026. Documents missing this information will be rejected by the tax authority, marking a shift to full enforcement of the new tax model. Taxpayers not prepared to generate these fields risk invoice rejections and significant business disruption, making system readiness critical.