Brazil: the option window for Simples Nacional in 2027 now closes on 15 October 2026; the IBS/CBS regular-regime choice runs to 30 October

Brazil: the option window for Simples Nacional in 2027 now closes on 15 October 2026; the IBS/CBS regular-regime choice runs to 30 October

29 September 2026: Brazil's Simples Nacional management committee (CGSN) has moved the deadlines for small businesses to choose how they will be taxed in 2027, the first year of the new consumption taxes under the tax reform. The changes come from CGSN Resolution 194, published in the Official Gazette on 28 September 2026, and are explained by the Receita Federal in a note dated 29 September.

Update, 6 November 2026: the option window closed on 15 October, and the regularisation and regular-regime deadlines fell on 30 October, so the advice below on those dates is now history. The cancellation window, 3 November to 20 December 2026, is open now under the same Resolution CGSN 194.

The two separate choices

The Receita Federal stresses that two different decisions are involved.

1. Opting into Simples Nacional for 2027 (micro and small businesses not yet in the regime):

• Apply between 1 September and 15 October 2026.
• If the application is refused because of debts or other problems, they can be regularised until 30 October 2026, a single deadline for everyone.
• The option can be cancelled between 3 November and 20 December 2026.
• It takes effect on 1 January 2027.

2. Choosing the regular IBS and CBS regime (companies already in Simples): under the reform, Simples companies may pay the new IBS and CBS taxes under the regular regime instead of within the Simples payment. The Receita gives the period up to 30 October 2026 for this choice for the first half of 2027, with cancellation possible from 3 November to 20 December.

The option for individual micro-entrepreneurs (Simei) stays in January 2027.

Who is affected

Brazilian micro and small businesses and their accountants, and the accounting, ERP and invoicing software vendors that serve them. Choosing the regular IBS/CBS regime changes how a company's invoices carry tax credits for its business customers, which affects B2B sales.

What to do

1. Decide before 15 October whether to opt into Simples for 2027, and before 30 October whether a Simples company should pay IBS/CBS under the regular regime.
2. Model the effect on prices and on customers who take tax credits.
3. Clear any debts that would block the option before 30 October.
4. Check that your invoicing software supports the new IBS/CBS fields for whichever regime you choose.

Sources

• Receita Federal: Simples Nacional 2027 - entenda os novos prazos e faça sua escolha com consciência e tranquilidade - 29 September 2026
• Diario Oficial da Uniao: Resolucao CGSN no 194, de 25 de setembro de 2026 (copy hosted by Fenacon) - 28 September 2026