The first mandatory operational milestone of Brazil's sweeping tax reform took effect today, August 3, requiring companies under the regular tax regimes of *lucro real* and *lucro presumido* to include new data fields for the dual value-added taxes (VAT) on all electronic invoices. Effective immediately, any *Nota Fiscal Eletrônica* (NF-e) or *Nota Fiscal de Consumidor Eletrônica* (NFC-e) that omits or incorrectly populates the fields for the federal Contribution on Goods and Services (CBS) and the state/municipal Tax on Goods and Services (IBS) is subject to automatic rejection by the tax authority’s systems, a shift that introduces a severe short-term compliance and business continuity risk for large Brazilian corporations.