Belgian E-Invoicing Mandate: The Readiness Paradox

Context

The Belgian e-invoicing mandate, which entered into force on September 2, 2026 for large enterprises and ETIs, represents a significant step in the country's efforts to modernize its tax-digitization landscape. This reform is part of a broader European trend toward electronic invoicing, aimed at improving VAT compliance and reducing fraud. The mandate requires these entities to emit invoices in a structured electronic format, while all Belgian enterprises must be capable of receiving electronic invoices. This obligation extends to micro-enterprises and VAT-exempt entities, ensuring comprehensive coverage across the business spectrum.

The reform comprises two pillars: e-invoicing (emission and reception of invoices in electronic format) and e-reporting (digital transmission of transaction and payment data to the tax administration). Since July 2025, Belgian enterprises have had the option to voluntarily adopt electronic invoicing ahead of the mandatory deadlines. The next key milestone is September 1, 2027, when smaller enterprises and micro-enterprises will be required to emit electronic invoices. As of September 7, 2026, no legislative changes or delays to this deadline have been reported.

What's Changing

The immediate change for large enterprises and ETIs is the mandatory emission of electronic invoices. This requirement obligates these entities to issue invoices in a structured electronic format, ensuring that the data can be directly processed by the tax administration. Additionally, all entities transacting with these companies must be able to receive electronic invoices, which necessitates that their systems are compatible with the new standards.

For transactions with end consumers (B2C), associations, and international clients, classical invoicing systems may still be used. However, transaction data must ultimately be transmitted digitally to the tax administration via e-reporting. This ensures that even excepted transaction types are covered under the reform's scope.

Implications for Belgian Enterprises

The readiness gap highlighted by the OpinionWay survey presents a systemic risk. Overconfidence among finance leadership may mask operational shortfalls precisely as the mandate goes live for the largest market participants. Enterprises must ensure their invoicing systems are fully compliant with the new regulations and that all relevant data can be transmitted electronically to the tax administration.

For large enterprises and ETIs, the immediate focus should be on achieving full compliance with the mandatory emission of electronic invoices. This includes updating their invoicing systems, training staff, and ensuring that all transaction data can be accurately captured and transmitted. Smaller enterprises and micro-enterprises should use the remaining time before their September 1, 2027 deadline to prepare for the mandatory emission of electronic invoices.

Outlook

The next key milestone is September 1, 2027, when the mandatory emission of electronic invoices will extend to smaller enterprises and micro-enterprises. As of September 7, 2026, no legislative changes or delays to this deadline have been reported. Enterprises should closely monitor any updates or changes in the legislation to ensure ongoing compliance.

The readiness gap identified by the OpinionWay survey underscores the need for enterprises to take proactive steps toward compliance. Addressing this gap will require a combination of system upgrades, staff training, and ongoing monitoring to ensure that all aspects of the e-invoicing mandate are met.