Tax Reform – Guidance on the entry into force of the IBS/CBS on January 1, 2026

By Ricardo Valim and José Martho.

On December 2, Joint CGIBS/RFB Notice No. 1/2025 was published, guidING on the main and ancillary tax obligations related to the triggering events for the new taxes created by the Tax Reform on Consumption for the year 2026, among which we highlight the following:

• As of January 1, 2026, taxpayers must issue electronic tax documents indicating the the IBS and CBS according to the rules and layouts of the published Technical Notes, being exempt from paying the new taxes. This rule applies to tax documents such as NF-e, NFC-e, CT-e, NFS-e, NF3-e, communication invoices and electronic tickets.
• Taxpayers for whom there is no defined accessory obligation will also be exempt from paying IBS and CBS. In this sense, tax documents still under construction or without a specific effective date, such as the Declaration of Specific Regimes (DeRE), the Real Estate Sale Invoice (NF-ABI), the Water and Sanitation Invoice (NFAg), the Gas NF-e, and the Air BP-e will have their layouts and effective dates defined in the future by technical notes or a joint act of the CGIBS and the RFB;
• The information to be provided by digital platforms will also have its layout and effective date defined in future technical notes or joint act of the CGIBS and the RFB;
• Individuals subject to IBS and CBS must register with the CNPJ starting in July 2026;
• Starting in January 2026, holders of ICMS costly benefits may apply for qualification on future compensation rights provided for in Article 384 of Complementary Law No. 214/2025. The electronic form shall be available on SISEN and must be filed via e-CAC.

Additionally, a few days ago, Technical Note 2025.002-RTC, version 1.33 (NT v 1.33), was published, bringing corrections to certain fields of the tax document templates provided for in previous Technical Notes, in addition to clarifying that, in January 2026, filling in the IBS/CBS fields will be optional and will no longer be a condition for the tax document to be issued.

NT v 1.33 also states that the “start of the mandatory reporting of new taxes (validation rule UB12-10)” is subject to “future implementation,” with no date yet set.

In other words, according to the provisions of this NT v 1.33, failure to fill in the new fields relating to IBS and CBS during January 2026 will not prevent the issuance of the electronic tax document. This measure was probably taken due to the difficulty many companies have faced in adapting to the new rules. Given this exemption, in January 2026, such companies will be able to issue their tax documents even if they are unable to correctly fill in the new fields resulting from the Tax Reform.

Despite the possibility of issuing tax documents as mentioned above, we cannot rule out that, in the future, tax authorities may question taxpayers who issued their tax documents without such information, since the legislation regarding the Tax Reform clearly states that, as of January 1, 2026, taxpayers must issue their tax documents with the information relating to the new taxes, even if the IBS/CBS does not need to be collected. It is also worth noting that Complementary Bill No. 108, which is currently being debated in Congress, provides that taxpayers who issue their tax documents incorrectly will have 60 days to regularize them after notification.

For this reason, we recommend that taxpayers who are able to issue their tax documents as of January 1, 2026, correctly fill in the fields relating to the new taxes, in order to avoid any future questions.

This bulletin is for informational purposes only and should not be considered as legal advice on any of the topics discussed herein. For additional information, please contact the leaders of the Tax Team. CGM Advogados. All rights reserved.