The tax reform is already in the implementation process, and the year 2026 is crucial for small and medium-sized enterprises to adjust their systems, tax documents, and procedures in view of the changes that will come into effect starting in 2027. Although the full transition extends until 2033, certain deadlines are approaching and require decisions or adaptations this year.
Preparation should not be solely the responsibility of the accountant or the tax department. It is necessary to also plan management systems, registries, invoice issuance, contracts, price definition, supplier and customer management, and cash flow. For Marcos Oliveira, an accountant and tax specialist, this change will affect various spheres of operation, impacting everything from buying and selling to negotiation and how values are passed on, influencing the cash balance of both the selling company and the supplier.
The timeline for the tax reform continues to be detailed and updated by the competent bodies, especially regarding operational rules and tax documents. The dates mentioned in this report reflect the guidelines in force at the time of publication and are subject to possible changes.
Given the imminent deadlines, the immediate step is to start internal preparation. Waiting for the following months may reduce the time available to identify flaws, make corrections, and test systems before the new rules take effect. Below are the essential points that small and medium-sized enterprises must analyze during this transition period.
Before modifying systems or making tax decisions, the company needs to understand how the new rules affect its core activities. Elements such as the adopted tax regime, the products and services traded, the profile of customers and suppliers, and the way credits can be utilized are factors that require consideration.
Marcos Oliveira advises conducting a specific simulation for the business itself, evaluating contracts, customers, and suppliers. He also suggests that the company understand how its partners are handling the reform, monitor market trends, and organize financially.
Guidance from José Homero Adabo
José Homero Adabo, financial director of Sescon Campinas, reinforces the need for entrepreneurs and accounting professionals to directly monitor the norms related to the reform. He points out that there are already legal provisions, regulations, and norms from the Management Committee regarding tax documents that must be studied to determine the best approach for each type of business.
It is essential that both the entrepreneur and the offices dedicate themselves to delving into these legal documents and finding the ideal way to serve the client.
For those who are not yet opted into the Simples Nacional and wish to join in 2027, the request must be filed between September 1st and 30th, 2026. This regime will take effect on January 1st, 2027. The request made in September can be canceled until the end of November, but such cancellation is definitive for the year 2027.
Companies already part of Simples and intending to remain in the regime do not need to request a new option for maintenance. However, in September, they have the option to pay IBS and CBS under the normal regime, outside of DAS, for the period from January to June 2027. If this choice is not made, the two taxes will remain in the Simples guide in the first semester, with a new chance to decide in March 2027 for the second semester.
Adabo specifically warns companies in Simples that sell to resellers. According to him, these businesses need to simulate various scenarios because the collection method can impact the credit received by the customer and, consequently, the supplier's competitiveness. He cites examples such as supply for auto parts, supermarkets, and stores.
Technological and Operational Challenges
Technology represents another vital area in preparation. For Roberta Marques, a tax lawyer and lawyer at the firm Araúz Advogados, the challenge goes beyond mere knowledge of legislation; it is about converting the new rules into functional processes in daily operations. Legislation only serves as a starting point, but the real challenge lies in transforming these norms into internal workflows.
Currently, an ERP can calculate taxes based on current legislation, but with the tax reform, this logic undergoes a complete transformation. Among the measures suggested by the lawyer are the review of product registration, fiscal classification, and system parameterization, in addition to testing with the usual business operations. She recommends simulating scenarios such as purchases, sales, returns, and bonuses before actual invoicing.
Marcos Oliveira highlights the attention required for companies that have implemented many customizations in their management systems. In these cases, a simple manufacturer update may be insufficient; it is necessary to map how previous modifications relate to the processes affected by the reform. The recommendation is not necessarily to replace the ERP, but rather to check with the supplier whether the software will be updated, identify integrations and customizations, and test the functionality of the processes.
Fiscal classification is another critical point. Roberta Marques warns that incorrect codes can lead to the rejection of invoices and generate rework. She advises linking each product to its correct code and verifying the applicable tax treatment. Marcos Oliveira adds that the supplier's tax regime can influence the purchasing company's ability to appropriate credits, requiring the registry to consider not only the item's characteristics but also the supplier's tax information.
Impact on Information and Cash Flow
Vinicius Panacho, a tax lawyer and partner at the firm Failla, Lima e Riva Advogados, associates this change with a significant increase in data contained in tax documents. He argues that the XML data may be used in more cross-references, increasing the importance of organizing the information that feeds the systems. There is much more information, given that the XML accommodates a large volume of data for cross-referencing.
The official timeline establishes distinct phases for the implementation of electronic tax documents linked to the reform, varying according to the type of document and the taxpayer. Companies must verify which rule applies to their operation and follow the disclosure of relevant layouts and validations. The calendar takes into account the need to adapt issuing systems and conduct preliminary tests.
There was a relevant change in August: the Federal Revenue and the IBS Management Committee clarified that the obligation to provide IBS and CBS information has not been suspended. What was postponed was the start of validations that could cause automatic rejection of documents due to the lack of specific fields. Thus, documents can be authorized even without all these fields in situations covered by the postponement of validations.
This does not negate the need for preparation. Systems still need to be adapted to the applicable layouts and rules, and companies must follow technical updates. For microenterprises and small businesses opting for Simples Nacional that provide services via NFS-e, there is a specific rule: the use of the National NFS-e Issuer will be mandatory on November 1st, 2026. The obligation for IBS and CBS for these taxpayers begins on January 1st, 2027.
Therefore, it is prudent to use the coming months to test routine operations, such as sales, purchases, returns, and bonuses. Beyond the tax sphere, the reform can influence commercial decisions. Marcos Oliveira recommends reviewing existing contracts and discussing with customers and suppliers how each party will handle the transition, as current generic tax clauses may be insufficient for the new scenario.
Pricing also requires analysis. Marcos Oliveira states that companies must simulate the impact of the reform on their own products and businesses. Roberta Marques, in turn, emphasizes that price, margin, and working capital must be considered when assessing the effects of the new taxation.
Cash flow is another concern raised by Marcos Oliveira, who lists financial organization for the new dynamic of tax collection among the necessary measures. Panacho relates this to the concept of split payment, explaining that part of the amount related to the tax can be sent to the government at the time of the transaction, instead of remaining temporarily in the company's cash register. In the case of split payment, the amount no longer enters the company's cash register; if a good costs one hundred, eighty-five enter, unlike in the past, where one hundred entered and the payment of fifteen was postponed.
The tax lawyer himself stressed that the functioning of this mechanism still depends on regulation. Therefore, for current planning, the issue should be included in financial planning without treating it as something completely consolidated, given what is still being regulated.
Preparation must also involve sectors that are not normally responsible for the tax part. Roberta Marques emphasizes that the reform is not exclusive to the tax or accounting sector, and that problems in document issuance can affect technology, finance, purchasing, logistics, contracts, and prices. Marcos Oliveira also considers it a mistake to leave all preparation in the hands of the accountant. While large corporations have internal teams or dedicated consulting firms for adaptation, small and medium-sized enterprises often wait for guidance from the accounting office. He states that this is the biggest mistake, and that the entrepreneur must be more engaged in it. This does not diminish the importance of accounting, as professionals will also need to adapt, and Adabo advocates for collaboration between the accountant and the tax lawyer, with distinct roles in interpreting the rules and in practical execution.
The company needs to define who will monitor the changes, which areas will be involved, and how information will be transmitted to those responsible for systems, tax, and finance. It is equally vital to follow updates from the responsible bodies, as rules and timelines continue to be detailed during the transition. For Marcos Oliveira, one of the biggest impediments to preparation is the belief that the reform is still distant, ignoring that it is a constant and ongoing reality.
