Resumo Legal – #2 Tax Reform Special

Second half – Setembro 2026

What are the latest developments in Brazil’s tax reform?

The second half of September brought important developments in Brazil’s tax reform, mainly the extension of the deadlines for small businesses to join the Simplified National Tax Regime (Simples Nacional) and, for companies already in that regime, to choose how they will calculate the IBS (the new state and municipal tax on goods and services) and the CBS (the new federal contribution on goods and services).

During this period, the Federal Revenue Service (Receita Federal) sent the Federal Court of Accounts (TCU) the calculation model that will be used to set the CBS reference rate. At the same time, the rates of the Excise Tax (Imposto Seletivo) entered their final stage of definition, and electronic service invoices (NFS-e) began to require IBS and CBS information for most services.

There was also progress on split payment, with the release of new operating manuals and the announcement of a testing phase with payment service providers. This edition also covers the guidance for cooperatives that wish to opt into their specific regime.

Below, we summarize the main developments of the period and their possible effects on taxpayers.

Deadlines extended for joining the Simplified National Tax Regime and for opting into the regular IBS and CBS regime for 2027

CGSN Resolution No. 194/2026, published in an extra edition of the Federal Official Gazette on September 28, 2026, and figures released by the Federal Revenue Service on September 30, 2026

In our previous edition, we discussed the deadlines to join the Simplified National Tax Regime and, within that regime, to choose how the IBS and the CBS will be calculated in 2027. Both deadlines were originally set to end on September 30 and have now been extended by CGSN Resolution No. 194/2026.

As a result, companies that are not yet in the Simplified National Tax Regime and wish to join it in 2027 now have until October 15, 2026 to file their request. Any pending issues that would prevent them from joining may be fixed until October 30, 2026.

For companies already in the Simplified National Tax Regime, the deadline to opt into the regular IBS and CBS regime was extended to October 30, 2026. The choice will still apply to the period from January to June 2027.

The resolution also set the period from November 3 to December 20, 2026 for cancelling either the request to join the Simplified National Tax Regime or the option for the regular IBS and CBS regime. Previously, cancellation was allowed until November 30.

According to figures released by the Federal Revenue Service on September 30, 2026, 817,461 requests to opt into the regular IBS and CBS regime had been filed up to that date.

Impact. The extension gives companies more time to assess their choices for 2027, especially regarding how the IBS and the CBS will be calculated. This allows a more detailed review of the expected tax burden and of the possible effects on credits, prices and business relationships before a decision is made.

Federal Revenue Service sends the TCU the model for calculating the CBS reference rate

Articles 349 to 353 of Complementary Law No. 214/2025 and statement by the Federal Revenue Service of September 14, 2026

The CBS reference rate will be set under the procedure established by Complementary Law No. 214/2025. This procedure involves the Federal Revenue Service, the TCU and the Federal Senate, and its goal is to keep federal revenue at the same level currently raised by the taxes that will be replaced.

On September 14, the Federal Revenue Service sent the TCU the model for calculating the rate that will apply in 2027. It clarified that the material does not include any estimate of the rate. The proposed rate will depend on the TCU’s technical review before it is submitted to the Federal Senate.

Under the announced schedule, the TCU must complete the calculations and send them to the Federal Senate by October 30. The Senate must then set the reference rate by resolution by December 15, to apply from January 1, 2027.

While the rate is still pending, the 2027 Annual Budget Bill, sent to Congress at the end of August, estimates CBS revenue of BRL 636 billion in its first year.

It is important to note that, until the Federal Senate publishes its resolution, the rates presented in studies and projections should be treated only as estimates. This is the case of the total rate of 27.91% (18.7% IBS and 9.21% CBS) used by the IBS Management Committee (CGIBS) in CGIBS Resolution No. 14/2026. That rate was used only to support the Committee’s own budget and financial calculations and does not anticipate the official reference rate.

Impact. Since the rate will probably be set only in mid-December, there will be little time to adapt before the CBS starts being effectively charged in 2027. Companies should therefore prepare alternative scenarios for pricing, review contract clauses and plan the configuration of their systems.

Excise Tax rates for 2027 are still pending

Complementary Law No. 214/2025, Article 150, III, “c”, of the Federal Constitution and estimates of the 2027 Annual Budget Bill

The Excise Tax was created by Complementary Law No. 214/2025 and will apply to goods and services considered harmful to health or to the environment, such as vehicles, vessels and aircraft, tobacco products, alcoholic and sugary drinks, and mineral goods. The tax will be charged from 2027, but the complementary law provides that its rates must be set by ordinary law.

The 2027 Annual Budget Bill estimates revenue of BRL 41.9 billion from this tax in its first year, even though the rates have not yet been defined. According to the Ministry of Finance, the goal is to keep, during this period, the tax burden currently associated with the IPI (the current federal tax on manufactured products) in the sectors affected.

With 2027 approaching, however, there is less time to define the rates. The Excise Tax is subject to the 90-day rule, which requires at least ninety days between the publication of the law and the start of collection.

Therefore, for the tax to be charged from January 1, 2027, the rule must be published in the first days of October 2026. If it is published later, the tax may only be charged after this ninety-day period has passed, otherwise taxpayers may challenge the collection.

As of the closing date of this edition, no rule setting the Excise Tax rates had been published. According to press reports, the provisional measure is expected to be issued only after the runoff election.

Impact. Without defined rates, it is harder for manufacturers, importers and distributors in the affected sectors to set prices, review contracts and adapt their systems for 2027. Companies should monitor when the rule is published and whether the 90-day rule is observed, as non-compliance may support court challenges to the start of collection.

NFS-e now requires IBS and CBS information for most services

RFB/CGIBS Joint Act No. 4 of July 30, 2026, and RFB/CGIBS Joint Act No. 1 of December 22, 2025

Since October 1, 2026, the electronic service invoice (NFS-e) must include IBS and CBS information for most services, according to the schedule set by RFB/CGIBS Joint Act No. 4/2026.

This stage covers services subject to the ISS (the current municipal service tax) and listed in the annex to Complementary Law No. 116/2003, except for the groups that follow their own schedule.

For some groups, the requirement starts on December 1, 2026. These include services provided or intermediated by digital platforms in the cases set out in the act, services under items 1.03, 1.05 and 1.09 of the list (such as data processing and hosting, and software licensing), and municipal public transport under item 16.01.

The December stage also covers leases, onerous assignments and rentals of real estate, rentals of movable goods, condominium fees, and supplies of intangible goods not subject to the ISS or the ICMS (the current state tax on goods), as well as other services listed in the act. For companies in the Simplified National Tax Regime, the requirement for the new taxes starts on January 1, 2027.

In 2026, the calculation of the IBS and the CBS is for information purposes only, and no payment is due as long as the related filing obligations are met, under the transition rules of RFB/CGIBS Joint Act No. 1/2025. Issuing the NFS-e correctly is part of these obligations and helps test the data and the calculation procedures for the IBS and the CBS during the trial period.

Impact. Service providers should check whether their invoicing tools and systems are ready to fill in the IBS and CBS fields correctly, including the tax classification of each transaction, according to the applicable schedule.

Split payment: new manuals approved and integration tests scheduled for October

RFB/SUARA/CGIBS/Executive Board Joint Technical Act No. 5 of September 22, 2026, and Federal Revenue Service Notice of September 30, 2026

The Federal Revenue Service and the CGIBS approved new technical documents for the Public Split Payment Platform. They describe how the system will operate, integrate, communicate and remain secure, and include the Operations, Integration, Timing, Network and Security manuals, as well as the openAPI specification.

The Operations Manual explains how the platform will connect payment service providers to the Federal Revenue Service and the CGIBS, allowing tax information to be exchanged and the taxes to be separated at the time of financial settlement. The separated amounts will then be transferred on a consolidated basis, by provider and by payment arrangement, with the CBS going to the Federal Revenue Service and the IBS going to the CGIBS.

The first phase, called Optional B2B, covers transactions between companies. Its use will be optional for whoever initiates the transaction, but implementation is mandatory for providers and operating institutions that take part in the payment arrangements covered. Credit, debit and prepaid cards, the simplified split payment model, payment by the buyer and the Excise Tax are not included in this phase.

Along with the approval of the manuals, the Federal Revenue Service announced that integration tests will start on October 15, 2026. The tests will take place in a controlled environment, with no final processing of transactions, no impact on real operations and no penalties for participants.

Providers interested in the first round must contact their industry associations by October 2. Other providers may register directly with the Federal Revenue Service and the CGIBS from November 16, using forms that will be available on November 13.

Impact. The tests do not yet change how companies pay their taxes, but the procedures described in the manuals already show possible effects on cash flow and working capital, since, with split payment, the supplier will receive the payment net of the IBS and CBS amounts that are separated.

Cooperatives may opt into the specific IBS and CBS regime until October 31

Federal Revenue Service/CGIBS Joint Guidance of September 18, 2026, based on Article 271 of Complementary Law No. 214/2025, Decree No. 12,955/2026 and CGIBS Resolution No. 6/2026

Complementary Law No. 214/2025 created an optional specific regime for cooperatives. Under it, the IBS and CBS rates are reduced to zero for the transactions listed in Article 271, which mainly cover supplies between the cooperative and its members.

In joint guidance released on September 18, the Federal Revenue Service and the CGIBS clarified that the option must be filed on the Federal Revenue Service Services Portal between September 1 and October 31, 2026, with effect from January 1, 2027. In addition to registering the choice, the cooperative must send a list of its members, with their identification and dates of admission. Simply expressing interest does not complete the process.

The option may be cancelled until October 31, 2026. Cooperatives that do not opt in during this period may do so in the next annual windows, in September and October, with effect from the following year.

Impact. The decision to opt in should take into account the specific features of the cooperative’s operations and the possible effects on tax credits, cash flow, pricing and relationships with members and customers, based on a simulation of the effects of the specific regime.

On the Radar

DATE	MILESTONE
15.10.2026	Simplified National Tax Regime. Deadline to opt into the regime for 2027. Split payment. Start of integration tests between payment service providers and the Public Split Payment Platform, with no impact on real operations.
30.10.2026	Simplified National Tax Regime. Final deadline to fix pending issues that prevent joining the regime and to opt into the regular IBS and CBS regime for the first half of 2027. CBS rate. Deadline for the TCU to send its calculations to the Federal Senate.
31.10.2026	Cooperatives. Final deadline to register the option for the specific IBS and CBS regime and send the list of members, with effect in 2027, or to cancel the option already made.
03.11 a 20.12.2026	Simplified National Tax Regime. Period to cancel the request to join the regime and the option for the regular IBS and CBS regime made for 2027.
16.11.2026	Split payment. Registration opens with the Federal Revenue Service and the CGIBS for other providers interested in the tests, with forms available from November 13.
01.12.2026	NFS-e. IBS and CBS information becomes mandatory for services under items 1.03, 1.05, 1.09 and 16.01 of the ISS list, digital platforms, rentals, condominium fees and other supplies included in the December schedule.
15.12.2026	CBS rate. Deadline for the Federal Senate to set, by resolution, the reference rate that will apply in 2027.
01.01.2027	CBS. Start of effective collection. Simplified National Tax Regime. IBS and CBS information becomes mandatory in tax documents issued by companies in the regime, and the options for the Simplified National Tax Regime and for the regular IBS and CBS regime take effect.

This newsletter is a biweekly publication of the tax practice of SouzaOkawa Advogados and does not constitute legal advice on specific cases. The application of the rules discussed here depends on the analysis of the particular features of each transaction. Our team is available to clarify the impacts of the changes presented.