How Peppol BIS Works in Belgium: Standards, Benefits & Setup

Belgium has mandated B2B electronic invoicing for all VAT registered businesses from January 2026. The government has chosen Peppol BIS Billing 3.0 as the required format for these e-invoices. 

Peppol BIS works by standardizing how electronic invoices are structured and exchanged between businesses. When businesses generate an invoice in your accounting or ERP software, it creates an XML file in the Peppol BIS format. This file contains all invoice details such as amounts, VAT, buyer and seller information in structured, machine-readable fields. The invoice is then validated against Peppol rules to ensure completeness and accuracy and sent to the supplier through Peppol network.

What is Peppol BIS 3.0 ?

Peppol BIS 3.0 is short for Peppol Business Interoperability Specification, version 3.0 is a standard for structuring e-invoices so they can be sent, received, and automatically processed by any compliant system. Think of it as a universal invoice template, developed internationally and now adopted by Belgium for all business invoicing.

Key facts about Peppol BIS 3.0:

• Built on EU standards: Peppol BIS is based on the European Norm EN 16931, which defines the minimum content and structure for e-invoices across the EU. If an invoice follows Peppol BIS, it automatically complies with EU law.
• Consistent, automated, machine-readable: By strictly defining how each field like supplier, buyer, tax, totals, etc, is presented, Peppol BIS eliminates guesswork and inconsistencies. Data is easily checked, imported, and stored.
• Structured, not a PDF: Peppol BIS invoices are pure data, specifically, XML files using a subset of UBL (Universal Business Language). No images or PDFs are attached, ensuring invoices can be processed without manual input.
• Originally for public sector, now for everyone: Peppol BIS started in B2G (business-to-government) e-invoicing, but Belgium is extending it to all B2B transactions for consistency and efficiency.
• Global reach: Peppol BIS is used in many European countries and is growing globally. For Belgian businesses, this means cross-border invoices can follow the same format.

How Peppol BIS Standardizes Electronic Documents in Belgium

Peppol BIS enforces a uniform way to create, send, and receive invoices. Every invoice is generated as a structured XML file, containing standardized tags for each piece of information: invoice number, dates, supplier and buyer details, line items, VAT breakdowns, totals, payment terms, and more.

• Every invoice looks the same to software: Regardless of which accounting or invoicing tool you use, as long as it outputs Peppol BIS, the file can be automatically processed by your customer’s system.
• Mandatory fields and business rules: Peppol BIS defines which fields are required, optional, or conditional (e.g., if a line has VAT exemption, you must include a reason code).
• No ambiguity: There’s no risk of missing information or fields being in the wrong place. Everything is predictable and validated before sending.
• Facilitates automation: Since all data is in agreed positions and formats, your systems can auto-book incoming invoices, automate VAT calculations, and handle approval workflows without human intervention.

How Peppol BIS Works in Practice

Peppol BIS enables your ERP or accounting software to send and receive invoices directly through the Peppol network. Integration is typically handled by a certified Access Point provider, like ClearTax, connecting your business systems to the entire e-invoicing ecosystem. Here is how it works: 

1. Invoice Creation: Your ERP or invoicing software generates an invoice as a Peppol BIS-compliant XML file. You don’t need to see the XML; it happens behind the scenes.
2. Validation: The software checks the XML against Peppol BIS rules. If anything is missing or incorrect, you are prompted to fix it.
3. Sending via Access Point: The validated invoice is sent through a Peppol Access Point (AP), which is either built into your software or provided by a third party.
4. Network Routing: The Access Point securely delivers your invoice to your customer’s Access Point, using Peppol’s international network.
5. Automatic Delivery: Your customer’s system receives the XML invoice, validates it, and can automatically enter it into their accounting or approval process.
6. Acknowledgements and Errors: If delivery fails (e.g., customer not registered), you receive a clear error. No lost invoices.
7. Processing: If your customer’s software supports Peppol BIS, their system can process the invoice instantly, no manual entry required.

Differences Between Peppol BIS and UBL

While Peppol BIS uses the UBL (Universal Business Language) syntax, they are not the same.

• UBL is a general XML standard for electronic business documents (like invoices, orders, etc.). It’s flexible and can be implemented in many ways.
• Peppol BIS is a strict profile of UBL, with additional business rules, field requirements, and validation specific to e-invoicing in Belgium and Europe.

Benefits of Using Peppol BIS for Businesses

Adopting Peppol BIS brings a range of operational, financial, and compliance advantages to Belgian companies. Here are the key benefits your business:

• Easy Legal Compliance: Using Peppol BIS means your invoices meet all Belgian and EU requirements, automatically.

• Full Automation: Data flows directly from system to system, reducing manual data entry and speeding up invoice cycles.
• Lower Costs: No more printing, posting, or manual processing of paper/PDF invoices.
• Better Accuracy: Data validation prevents errors and reduces disputes.
• Faster Payments: Automated processing can lead to quicker approval and payment from customers.
• Single Format for All Partners: You don’t need to manage different invoice templates for different clients.
• Scalable & Future-Ready: Works for cross-border EU invoices and supports future digital mandates.
• Improved Audit Trail: Digital invoices are easy to archive, search, and present during VAT or financial audits.

Implementing Peppol BIS E-invoicing in Your Business

Here’s how your business can successfully implement Peppol BIS:

1. Check your software: Confirm that your current invoicing, ERP, or accounting software supports the Peppol BIS format. Many leading systems now offer Peppol integration.
2. Connect to a Peppol Access Point: You can do this via your software provider, a third-party service, or, for very large companies, by becoming your own Access Point.
3. Set up master data: Ensure your customer and supplier records are complete VAT numbers, company names, addresses, etc as required by Peppol BIS.
4. Test your setup: Pilot test the process with a few customers and suppliers before going live with everyone.
5. Train your staff: Make sure your accounting, billing, and IT teams know how the new process works and how to resolve validation issues.
6. Be ready to receive as well as send: After 2026, you must be able to receive Peppol BIS e-invoices from your suppliers.
7. Leverage support: Use guides from the Belgian government or your software/access point provider for help and best practices.

Conclusion

Peppol BIS is a strict, EU-compliant standard that structures invoice data as machine-readable XML, enabling automated validation, delivery, and processing across different software platforms. This eliminates the need for manual data entry, reduces errors, and ensures invoices meet all legal requirements for both Belgian and cross-border transactions.

Setting up Peppol BIS involves ensuring your software/ ERP is integrated to a Peppol Access Point with the help of Peppol Accredited Service Provider (ASP) like ClearTax, and preparing your master data.