Belgian VAT Code for E-Invoicing: Types, Standards, and Implementation

Starting from January 1, 2026, all VAT-registered businesses in Belgium will be required to issue and receive structured electronic invoices for domestic B2B transactions. One of the core objectives of Belgium’s e-invoicing mandate is to ensure that all the transaction related documents including VAT related details such as the supplier and buyer VAT IDs, VAT category codes, applicable rates, exemption reasons, etc are captured in a structured, machine readable format. 

Therefore, these VAT specifics are not expressed as free text but instead are encoded using standardized codes, which enable seamless automation, accurate validation, and real time compliance checks across different software and tax systems. The selection and use of these codes are governed by established frameworks and standards, including EN 16931 and Peppol BIS.

Understanding Codes in Belgian E-Invoicing

While free text may seem natural for human readers, it introduces significant problems for digital processing, especially when large volumes of invoices need to be handled automatically. When actual text is used, the same information can be written in countless different ways.

 For example, “Standard VAT,” “standard vat,” “standard tax rate,” or “21% normal.” 

To a human, these all mean the same thing. However, for a computer or an automated accounting system, each unique text entry is treated as a separate value. This creates fragmented, unstructured, and non-homogeneous data that cannot be reliably grouped, searched, or interpreted in bulk.

Problems of Using Free Text instead of Standard Codes

With free text, machines cannot:

• Group transactions that share the same VAT treatment but are described differently.
• Run consistent calculations or apply tax rules accurately.
• Validate invoices efficiently, since every variation must be manually mapped or interpreted.
• Integrate data seamlessly across borders, systems, and languages.

Consequences

If free text fields are used instead of codes, the whole purpose of truly electronic invoice is defeated and creates the same problem as invoice data consolidated in an excel spreadsheet

• Data silos (where identical items are separated because of text differences),
• Manual intervention (slowing down processes and increasing error risk), and
• Inefficiency at scale (what works for one invoice fails for thousands).

How Codes Solve this Problem?

Codes solve all these problems by providing a fixed, universally recognized value for each specific meaning. For instance, the code “S” always means “Standard VAT Rate” no matter what language, company, or system is used. This ensures that:

• Every system group and interprets data identically,
• Bulk processing, analytics, and compliance checks are accurate and automated,
• Cross-border transactions are frictionless, since codes are part of global or European standards,
• Data is structured and homogeneous, making it instantly machine-readable and actionable.

Example of Codes Used in E-Invoicing

• Item Classification Codes: Standardize the description of goods and services (e.g., UNSPSC, CPV, HSN codes).
• Country Codes: Identify the country of the supplier or buyer (e.g., “BE” for Belgium).
• Document Identifier Codes: Specify the document type, such as “380” for an invoice or “381” for a credit note (according to UBL and Peppol standards).
• VAT Category Codes: Indicate how VAT applies to each line item (e.g., “S” for standard rate, “E” for exempt, “AA” for Belgian reverse charge in construction).
• Currency Codes: Indicate the transaction currency using ISO 4217 (e.g., “EUR” for Euro).

VAT Details Required for e-Invoicing in Belgium

The following VAT-specific details are required on Belgian e-invoices:

1. Supplier and buyer VAT identification numbers (VAT IDs)
2. VAT category codes for each invoice line, indicating how the transaction is treated for VAT purposes (e.g., standard rate, exemption, reverse charge)
3. VAT rates applied per line item (e.g., 21%, 6%, 0%)
4. VAT exemption codes and textual reasons (where applicable)
5. VAT amounts per rate/category
6. Legal declarations for specific scenarios such as reverse charge

Frameworks and Standardization Requirements

The VAT codes and their technical representation on Belgian e-invoices are determined by a set of harmonized European frameworks and standards, including:

• EN 16931 (European Norm 16931): Defines the semantic data model for e-invoices in the EU, specifying what VAT information and codes must be present.
• Peppol BIS (Business Interoperability Specification): Provides detailed guidelines and validation rules for exchanging invoices via the Peppol network, including the use of VAT codes, exemption reasons, and data formats.
• UBL (Universal Business Language): The XML-based syntax in which Belgian e-invoices are structured, ensuring machine readability and automatic data exchange.
• CUIS (Core Invoice Usage Specification): Belgium adds specific extensions (CIUS) to EN 16931 to accommodate national VAT rules, such as special reverse charge codes for construction services or domestic nuances for intra-community supplies.

VAT code for e-Invoicing in Belgium

The following sections explain, in clear and simple terms, the most important VAT-related codes and requirements for e-invoicing in Belgium.

Supplier and Buyer VAT Identification Numbers (VAT IDs)

Belgian and EU VAT law mandates that both supplier and buyer VAT identification numbers are clearly stated on every e-invoice. 

VAT Category Codes for Each Invoice Line

Every invoice line in Belgian e-invoicing must carry a VAT category code indicating the tax treatment of that transaction. These codes are standardized as per EN 16931 and extended by Belgian law.

VAT Rates Applied Per Line Item

Each invoice line specifies the VAT rate (%) applied to that good or service. Belgium’s main VAT rates are 21% (standard), 12%, 6%, and 0% (for specific cases). 

VAT Exemption Codes and Textual Reasons

If a transaction is exempt from VAT, you must show both a code and a short explanation of the legal reason. This is required for the buyer, tax authority, and audits.

VAT Amounts Per Rate/Category

The invoice must show the VAT amount for each VAT rate or category, giving full transparency.

* For reverse charge, VAT is shown as zero on supplier invoice; buyer self-declares VAT.

Legal Declarations for Specific Scenarios

Where a transaction is exempt from VAT (e.g., exports, healthcare, intra-community supplies), the invoice must include:

• A VAT exemption code (EN 16931/Peppol/Belgian CIUS list)
• A textual reason referencing the legal justification

How Should Businesses Comply?

Trying to manage Belgian (and EU) e-invoicing entirely in-house, coding your own formats, handling validations, and connecting to Peppol, is highly complex and risky. The rules are strict, the formats are technical, and mistakes can lead to rejected invoices or tax fines. That’s why businesses need rely on specialized Peppol Accredited Service Providers like ClearTax.

How can ClearTax Help You?

ClearTax is a a Certified Peppol Access Point (AP) that lets you send and receive e-invoices in the standardized, legally compliant Peppol format. Here is what ClearTax does for your business

• Integrate with your ERP/accounting system (SAP, Microsoft Dynamics, Odoo, Oracle, etc.)
• Map your invoice data to the correct Peppol and Belgian codes (VAT ID, VAT category, exemption, etc.)
• Enrich and validate the invoice, checking for missing data, mandatory notes, correct tax treatment, etc.
• Convert and format your invoice into the proper XML (UBL) file, using the EN 16931 and Belgian CIUS standards.
• Transmit securely via the Peppol network, ensuring your invoice reaches the customer (and, from 2028, the tax authority).

What Businesses Need To Do?

Here are the steps you should follow to comply

1. Choose a certified Peppol Access Point (like ClearTax).
2. Connect your ERP/accounting system to the AP’s platform, usually a one-time integration.
3. Ensure correct VAT information is entered in your ERP (supplier/buyer VAT IDs, product/service types, rates).
4. Train your team on new processes and get support from your provider.
5. Let the AP handle the rest, mapping, validation, formatting, legal compliance, and transmission.

Conclusion

Using these standardized codes helps overcome common problems that occur with free text fields, such as inconsistent data entry, processing errors, and difficulties handling large volumes of invoices. Codes allow every accounting or tax system to interpret information the same way, ensuring that e-invoicing data is always interoperable, ready for audits, and suitable for cross-border business. Belgian e-invoices must now always include the correct VAT codes, rates, amounts, and any required legal notes or exemption justifications, all formatted according to harmonized e-invoicing models.