Mandatory National NFS-e for Simples Nacional Starting November 1st: What Tax and IT Teams Need to Adjust Now

Less than three weeks to the switch: National NFS-e Issuer becomes mandatory for Simples Nacional

There are only a few days left until a significant operational change in service invoice issuance in Brazil. Starting November 1, 2026, microenterprises (ME) and small businesses (EPP) opting for Simples Nacional that provide services subject to NFS-e will no longer be able to issue invoices through municipal systems and will be required to use the National NFS-e Issuer.

From September to November: the history of the change

In April 2026, CGSN Resolution No. 189/2026 had set September 1, 2026, as the deadline for Simples Nacional companies to start issuing NFS-e exclusively through the National Issuer. In August, however, the Simples Nacional Steering Committee published CGSN Resolution No. 191, of August 4, 2026, which expressly revoked the previous resolution and postponed the deadline to November 1, 2026. The resolution was published in the Federal Official Gazette on August 10.

What changes in practice

Starting in November, Simples Nacional companies that provide services subject to NFS-e issuance will be required to use the National NFS-e Issuer, available both through the web application and via API (Application Programming Interface) integration. For those already operating with an integrated ERP, the natural path is the API: the system builds the DPS (Service Provision Declaration), signs it with a digital certificate, and transmits it to the national environment, which returns the authorized invoice with the access key. Communication requires an ICP-Brasil certificate and a signed XML; to issue invoices without human intervention, the certificate must be an A1, in file format.

Another point that deserves IT teams' attention: gov.br login, which in the National Issuer only works for MEI. For ME and EPP, access and registration follow their own workflow — it's worth testing institutional access in advance to avoid blocking issuance on the first business day of November.

Nationwide validity and specific situations

The national-standard NFS-e will be valid throughout Brazilian territory, which simplifies matters for companies providing services in more than one municipality. The rule also covers a case that often raises questions: the ME or EPP must use the National NFS-e Issuer even when its enrollment in Simples Nacional is pending or being discussed administratively or judicially, provided the decision could result in the company's retroactive inclusion in the regime.

On the other hand, the obligation has a clear scope limit: companies whose operations are taxed exclusively by ICMS, such as the trade of goods, follow the product invoice rule and are not covered by this specific NFS-e requirement.

November is not January: separate issuance from taxation

A point worth emphasizing to avoid rework on configuration: the specific CBS and IBS rules for those under Simples Nacional will only take effect as of January 1, 2027 — the November mandate deals only with the invoice issuance method, not with taxation itself. In other words, starting November 1, the issuance channel changes; the IBS and CBS line items on the Simples Nacional NFS-e will only come into play at the beginning of 2027, according to the calendar already released by the Federal Revenue Service and the IBS Steering Committee.

Technical checklist for tax, accounting, and IT teams

• Map all Simples Nacional clients or business units that currently issue NFS-e through the city hall's system;
• Decide whether issuance will be done through the national web issuer or via API integration and confirm with ERP vendors the availability of integration with the National Issuer.
• Review the service registry, taxation codes, municipality of incidence, withholdings, customer data, ERP integration, and API issuance when used.
• Validate the A1 digital certificate for automated issuance via API, without relying on manual portal login;
• Companies that issue many invoices need to validate the API, digital certificate, permissions, and integration with the management system in advance, since a billing failure can impact collections and customer service.
• Run end-to-end issuance tests before November 1, including contingency scenarios.

For companies using Odoo via Edoo, it is recommended to confirm with the implementation team whether NFS-e issuance for Simples Nacional clients is already pointing to the National Issuer and to run at least one test invoice in each relevant municipality before the switch.

This content is informational and does not replace guidance from the accounting firm responsible for your company. For decisions regarding tax framework, assessment regime, and tax configuration, always consult your accountant.

Need help validating your NFS-e operation before November 1? Talk to Edoo.