Constitutional Amendment 132/2023 and Complementary Law 214/2025 create the CBS, a federal tax, and the IBS, a tax of the States and Municipalities. The CBS replaces PIS and Cofins. The IBS replaces ICMS and ISS, gradually. The Simples Nacional regime for small businesses also changes, and Complementary Law 227/2026 amended parts of the reform, including the rule on free trade zones.

The CBS takes effect in 2027. The IBS starts at a symbolic rate in 2027 and 2028, and ICMS and ISS are phased down from 2029 to 2032 (articles 126 to 128 of the Transitional Constitutional Provisions).

Who feels the change first

• Companies under Lucro Real and Lucro Presumido. They start calculating CBS and IBS by credits and debits, with broad credit on purchases. The cost and pricing calculation needs to be redone.
• Simples Nacional taxpayers. CBS and IBS become part of the DAS split. CGSN Resolution 190/2026 sets out the tables of Annexes I to V for 2027 and 2028, and the company may choose to pay IBS and CBS under the regular regime, on the Simples Nacional Portal, in September (effective January) or in March (effective July). The choice is irrevocable within the semester and keeps applying in later periods until the company opts out.
• Importers and free trade zone companies. The incentives follow their own rules (articles 459 to 467 of Complementary Law 214/2025). See the page on the Macapá and Santana Free Trade Zone.
• Health. Health services get a 60% reduction in IBS and CBS rates (article 130 of Complementary Law 214/2025), and professionals and clinics need to check that the service is on the legal list.

What to do now

1. Map the company’s transactions by type: sale of goods, services, imports, transactions inside the free trade zone.
2. Simulate the 2027 and 2028 burden with the rates available and compare it with the current burden.
3. Review long-term contracts, which may need a price adjustment clause because of the change of tax.
4. Under Simples Nacional, compare the DAS with the regular IBS and CBS regime before the option windows (September, for January, and March, for July).
5. Check registrations and authorisations, such as the Suframa registration for those who use the free trade zone incentives.

Limits of the simulation

The CBS and IBS rates still depend on being set and regulated, and may change. Any figure should be treated as an estimate until the final definition. The firm’s clients use its own calculator, which shows the caveat about these rates in every result.