How Belgium's 2026 E-Invoicing Obligation Impacts Luxembourg Businesses

Belgium's 2026 Mandate: A Game Changer for the Region

Starting in January 2026, Belgium will require all VAT-registered businesses to send and receive B2B invoices electronically via the Peppol network. This is one of the most comprehensive e-invoicing mandates in Europe, and its effects will extend far beyond Belgium's borders.

For Luxembourg, Belgium's closest economic partner, the implications are profound. The two countries share deep commercial ties: thousands of businesses trade across the border daily, over 50,000 Belgian residents commute to the Grand Duchy for work, and many companies operate in both markets simultaneously.

If your business has any commercial relationship with Belgian companies, the 2026 obligation will affect you directly. Understanding and preparing for this change is essential.

What Exactly Is Belgium Requiring?

The Belgian mandate requires that from 1 January 2026, all B2B invoices between Belgian VAT-registered businesses must be exchanged electronically through the Peppol network. Key points include:

• Scope: All VAT-registered businesses in Belgium, regardless of size
• Channel: Peppol is the designated network for B2B e-invoicing
• Format: Invoices must comply with the EN 16931 European standard
• No exemptions: Freelancers, SMEs, and large enterprises are all included
• Cross-border: Belgian businesses will increasingly expect their foreign suppliers, including companies here, to be Peppol-ready

While the legal obligation applies to transactions between Belgian VAT-registered entities, the practical effect is that any business trading with Belgium will need to support Peppol to maintain smooth commercial relationships.

How This Affects Local Businesses

The impact on businesses in the Grand Duchy manifests in several ways:

Direct Suppliers to Belgian Companies

If you supply goods or services to Belgian companies, your clients will expect, and may require, you to send invoices via Peppol from 2026 onwards. While you are not legally bound by Belgian law, a Belgian client who is obligated to receive structured e-invoices may simply stop accepting PDF invoices from their suppliers.

Receiving Invoices from Belgian Suppliers

Belgian businesses supplying goods or services to your company will be sending Peppol invoices. To receive and process these efficiently, you will need a Peppol access point. Without one, you may face delays and manual workarounds that cost time and money.

Competitive Pressure

As the Belgian market standardises on Peppol, businesses that are not connected may find themselves at a competitive disadvantage. Belgian companies may prefer suppliers who can exchange invoices electronically, as it reduces their own processing costs and compliance burden.

Supply Chain Effects

The mandate creates a ripple effect through supply chains. Even if your direct clients are domestic, they may have Belgian clients who require them to be on Peppol, creating indirect pressure that flows up the supply chain to your business.

The Economic Relationship Between the Two Countries

To understand the scale of the impact, consider the economic ties:

• Belgium is one of the Grand Duchy's top trading partners, both for imports and exports
• Over 50,000 Belgian cross-border workers commute here daily
• Many businesses operate in both countries, with offices or clients on each side of the border
• The Benelux economic area facilitates deep integration between the two markets
• Shared language communities (French-speaking Belgium and francophone communities locally) further strengthen commercial ties

Given this level of interconnection, the Belgian mandate is not an abstract foreign regulation for businesses here. It is a practical reality that will affect daily operations.

Preparing Your Business

The good news is that preparing for the Belgian mandate also strengthens your position on the local market. Here is a practical roadmap:

Step 1: Assess Your Belgian Exposure

Identify all your business relationships with Belgian companies, both as a supplier and as a buyer. Estimate the volume of invoices exchanged across the border to understand the scale of the change.

Step 2: Connect to Peppol

Choose a certified Peppol access point like Peppol Box and register your business on the network. This gives you the ability to both send and receive e-invoices via Peppol, covering your Belgian and domestic B2G obligations in one go.

Step 3: Inform Your Partners

Let your Belgian clients and suppliers know that you are Peppol-ready. Share your Peppol ID so they can direct their e-invoices to you. This proactive communication demonstrates professionalism and makes the transition smoother for everyone.

Step 4: Integrate with Your Systems

If you use accounting software, explore integration options with your Peppol access point. Peppol Box offers multiple connection options including its web portal, mobile apps, CSV/XML/PDF export, and an API available for automation. With Flexina Sync, your accountant can also automatically retrieve your invoices from Peppol Box — free of charge.

Step 5: Leverage Financial Aid

The SME Packages Digital programme offers up to 70% subsidies for digitalisation projects, including e-invoicing implementation. Apply before connecting to Peppol to maximise your financial benefit. The Chamber of Commerce can guide you through the application process.

One Solution for Two Markets

The beauty of Peppol is that it is a single, European-wide network. By connecting to Peppol through a provider like Peppol Box, you simultaneously:

• Comply with the domestic B2G e-invoicing mandate (in effect since March 2023)
• Prepare for Belgium's B2B e-invoicing mandate (effective January 2026)
• Enable e-invoicing with partners across all 30+ Peppol-connected countries
• Future-proof your business for upcoming EU-wide e-invoicing requirements under the ViDA initiative

There is no need for separate solutions for each country or market. One Peppol connection covers everything.

The Time to Act Is Now

January 2026 may seem distant, but businesses that wait until the last moment often face rushed implementations, limited provider availability, and no time to train their teams. By starting now, you can:

• Test your setup thoroughly before the deadline
• Train your staff at a comfortable pace
• Resolve any integration issues in advance
• Take advantage of government subsidies while they are still available
• Build confidence with cross-border Peppol invoicing before it becomes mandatory