Mandatory Details on a Belgian Invoice (2026)

In Belgium, an invoice is far more than a commercial document: it is a legal document whose content is strictly regulated. Missing even one mandatory detail can lead to your client's VAT deduction being refused, administrative fines for you, and complications during a tax audit. This comprehensive guide lists every invoice requirement to include on your invoices in 2026, with concrete examples and precise legal references.

The Legal Framework

Invoice requirements in Belgium are defined by several legal texts:

• Article 5 of Royal Decree No. 1 of 29 December 1992: the list of mandatory details on VAT invoices
• Article 53 of the VAT Code (CTVA): the obligation to issue invoices
• Article III.74 of the Code of Economic Law (CDE): obligations relating to a company's business documents
• European Directive 2006/112/EC (VAT Directive): the harmonised EU-level framework
• Law of 6 February 2024: the obligation to issue B2B electronic invoices via Peppol

Invoice Requirements: The Complete and Detailed List

1. The Invoice Date

The date the invoice is issued must be clearly stated. For VAT purposes, the invoice must be issued by no later than the 15th day of the month following the month in which the goods were delivered or the services performed (art. 53, para. 2 CTVA).

Example: a service carried out on 20 March 2026 must be invoiced by 15 April 2026 at the latest.

2. The Invoice Number

Every invoice must carry a unique sequential number that identifies it unambiguously (art. 5, para. 1, 3 of Royal Decree No. 1). The numbering must be continuous, with no gaps or duplicates.

Accepted formats:

• F-2026-001, F-2026-002, etc.
• 2026/001, 2026/002, etc.
• 20260001, 20260002, etc.

Important: you may use several numbering series (by activity, by point of sale), provided each series is continuous and there is no ambiguity.

3. Full Identification of the Supplier (Issuer)

The following information must appear on the invoice:

For self-employed individuals: state your full name, your business address (or home address), and your CBE/VAT enterprise number.

CDE obligation: article III.74 of the Code of Economic Law requires that all of a company's documents (including invoices) state the company name, legal form, registered office and enterprise number. For SRLs and SAs, share capital or equity must be stated on deeds, but not necessarily on invoices.

4. Full Identification of the Client (Recipient)

Special case: if the client is not VAT-registered (a private individual), you do not need to state their VAT number, but their identity and address remain mandatory.

5. Date of Delivery or Performance

The date on which the goods were delivered or the service was completed must be stated if it differs from the invoice date (art. 5, para. 1, 4 of Royal Decree No. 1).

For continuous services (subscriptions, maintenance contracts), state the period covered by the invoice.

6. Detailed Description of the Goods Delivered or Services Provided

The description must be sufficiently precise to allow the nature of the transaction to be identified (art. 5, para. 1, 6 of Royal Decree No. 1). Vague descriptions such as "services rendered" or "miscellaneous" are insufficient and can lead to the client's VAT deduction being refused.

Examples of compliant descriptions:

• "Development of a showcase website – 5 pages – as per quote No. 2026-015 of 01/02/2026"
• "Repair of a Vaillant model X boiler – circulator pump replacement – 2 hours' labour"
• "Legal advice – drafting of general terms and conditions of sale – 4 hours"

Examples of non-compliant descriptions:

• "Services rendered"
• "March 2026 fees"
• "Miscellaneous work"

7. Quantity and Nature of the Goods or Scope of the Services

For each invoice line, specify:

• The quantity (number of units, hours, days, m², kg, etc.)
• The unit price excluding VAT
• Any discounts (rebates, allowances, early-payment discounts)

8. The Taxable Amount (Amount Excluding VAT)

The total amount excluding VAT must be stated, broken down by VAT rate if several rates apply to the same invoice.

9. The Applicable VAT Rate

The applicable VAT rate(s) must be clearly indicated for each line or group of lines:

10. The VAT Amount

The VAT amount must be stated in euros (EUR), broken down by rate if several rates apply. This amount must be calculated on the corresponding taxable amount.

11. The Total Amount Payable (Including VAT)

The total amount including all taxes must be clearly displayed.

12. The Currency

Amounts must be expressed in euros (EUR). If the invoice is drawn up in another currency (for a foreign client, for example), the VAT amount must nevertheless be converted into euros at the exchange rate on the date the tax becomes due (art. 27 CTVA).

Situation-Specific Details

Beyond the standard invoice requirements listed above, certain transactions call for additional wording.

Reverse Charge – Intra-Community Transactions

For intra-Community supplies of goods (art. 39bis CTVA):

• Wording: "VAT exemption – Intra-Community supply – Article 39bis of the VAT Code"
• The client's VAT number in the other member state must be stated
• The transaction must be included in the intra-Community return (statement of intra-Community transactions)

For intra-Community B2B services (art. 21, para. 2 CTVA):

• Wording: "Reverse charge – VAT due by the recipient – Article 21, para. 2 of the VAT Code"

Co-Contractor Scheme (Construction Subcontracting)

For certain transactions in the construction sector (art. 20 of Royal Decree No. 1), VAT is due by the co-contractor (the client, if VAT-registered):

• Wording: "Reverse charge – VAT payable by the co-contractor – Article 20 of Royal Decree No. 1"
• The supplier does not charge VAT
• The client declares it in their own VAT return

VAT Exemption Scheme (Small Businesses)

If you are subject to the exemption scheme (art. 56bis CTVA, turnover below EUR 25,000):

• Wording: "Small business subject to the VAT exemption scheme. VAT not applicable."
• No VAT stated on the invoice
• No VAT number required (but the CBE enterprise number remains mandatory)

Margin Scheme (Second-Hand Goods)

For sales of second-hand goods under the margin scheme (art. 58, para. 4 CTVA):

• Wording: "Margin scheme – Second-hand goods – Article 58, para. 4 of the VAT Code"
• VAT is not stated separately

Exports Outside the EU

For exports of goods outside the European Union (art. 39 CTVA):

• Wording: "VAT exemption – Export – Article 39 of the VAT Code"
• VAT at 0%

Deposit Invoice

A deposit triggers VAT liability at the moment it is received (art. 22bis CTVA). The deposit invoice must:

• State that it is a deposit (not the total price)
• Show the deposit amount excluding VAT, the VAT, and the amount including VAT
• Refer to the quote or contract

6% VAT for Property Renovation Work

For renovation work on a private home over 10 years old at the reduced rate of 6%:

• The VAT certificate signed by the client (project owner) must be kept by the contractor
• Invoice wording: "6% VAT rate – Renovation work on a residential building whose first occupation took place at least 10 calendar years before the date of the first invoice for this work – Article 1quinquies of Royal Decree No. 20"

Self-Billing

In certain cases, a VAT-registered business must issue a self-invoice (art. 12, para. 1 and 19 CTVA), notably when withdrawing company goods for private use.

Payment Terms

Although payment terms are not part of the core invoice requirements under Royal Decree No. 1, they are strongly recommended and often required by the general terms and conditions of sale.

State at least:

• The payment term (e.g. 30 days from the invoice date)
• The bank account number (IBAN + BIC)
• The structured reference (Belgian VCS/OGM: +++XXX/XXXX/XXXXX+++)
• Late-payment penalties: under the law of 2 August 2002, the B2B late-payment interest rate is the ECB rate + 8 points (around 12.50% in 2026)
• The flat-rate recovery compensation (minimum EUR 40)

The Belgian Structured Reference (VCS/OGM)

The structured reference is a Belgium-specific format that allows payments to be reconciled automatically:

Format: +++XXX/XXXX/XXXXX+++

Two calculation methods:

• Based on the invoice number: the first 10 digits correspond to the invoice number, the last 2 are the modulo 97 check
• Based on the client number + invoice: customisable according to your system

Your Belgian invoicing software generates this structured reference automatically.

Full Example of a Compliant Belgian Invoice

The layout below brings together all the invoice requirements described above.

===========================================================
                    INVOICE
===========================================================

WebDev Solutions SRL
Rue de la Loi 42, 1000 Brussels
CBE: 0789.456.123
VAT: BE 0789.456.123
IBAN: BE42 3100 1234 5678 - BIC: BBRUBEBB

-----------------------------------------------------------

INVOICE TO:
Boulangerie Artisanale Martin SRL
Avenue Louise 156, 1050 Ixelles
VAT: BE 0456.789.012

-----------------------------------------------------------

Invoice No.: F-2026-042
Invoice date: 15 March 2026
Service period: 01/02/2026 to 10/03/2026

-----------------------------------------------------------

DESCRIPTION                    QTY    UNIT PRICE   TOTAL
-----------------------------------------------------------
Showcase website design         1    2,500.00    2,500.00
  5 pages, responsive design
  As per quote No. D-2026-015

Online booking module            1      800.00      800.00
  integration with payment

User training (2h)              2h     100.00      200.00

Annual web hosting               1      180.00      180.00
  Pro package - 20 GB
-----------------------------------------------------------

SUBTOTAL EXCL. VAT                             3,680.00 EUR
VAT 21%                                          772.80 EUR
-----------------------------------------------------------
TOTAL INCL. VAT                                4,452.80 EUR
===========================================================

PAYMENT TERMS:
Term: 30 days from invoice date
Due date: 14 April 2026
Account: IBAN BE42 3100 1234 5678
Structured reference: +++042/0000/04972+++

In the event of late payment, late-payment interest of
12.50% and a flat-rate compensation of 10% (min. EUR 40)
will apply automatically (law of 2 August 2002).

Penalties for Non-Compliant Invoices

VAT Fines

The VAT administration can impose administrative fines for failure to meet these invoice requirements:

These amounts are set by the Royal Decree of 28 December 1999 determining non-proportional tax fines in VAT matters (annex, section 3).

Consequences for the Client

If your invoice does not include all the mandatory details, your client risks having their VAT deduction refused. Article 45, para. 1 of the CTVA requires a compliant invoice to exercise the right to deduct. This can damage your business relationships.

Consequences for Income Tax

A non-compliant invoice can also lead the tax administration to reject the deduction of the corresponding business expenses (art. 49 of the Income Tax Code 1992).

Electronic Invoicing in 2026

The Peppol Obligation

The same invoice requirements apply under Peppol, only in structured form. Since 1 January 2026, all B2B invoices between VAT-registered Belgian businesses must be issued in structured electronic format via the Peppol network (law of 6 February 2024). The format is Peppol BIS Billing 3.0 (based on UBL 2.1).

Invoice Requirements Within a Peppol Invoice

Peppol invoices contain the same mandatory details, but in a structured (XML) format. The main fields are:

• AccountingSupplierParty: supplier identification
• AccountingCustomerParty: client identification
• InvoiceLine: invoice lines with descriptions, quantities and prices
• TaxTotal: VAT amounts
• LegalMonetaryTotal: financial totals
• PaymentMeans: means of payment (IBAN, structured reference)

B2C Invoices: No Peppol Obligation

Invoices addressed to private individuals (non-VAT-registered) are not subject to the Peppol obligation. You can continue to issue them on paper or as a PDF.

Checklist: Is Your Invoice Compliant?

Use this checklist to confirm your invoice meets every invoice requirement before you send it:

• Invoice date
• Unique sequential number
• Supplier's name/company name and address
• Supplier's legal form
• Supplier's enterprise number (CBE)
• Supplier's VAT number
• Client's name/company name and address
• Client's VAT number (if VAT-registered)
• Detailed description of goods/services
• Quantities and unit prices
• Taxable amount (excl. VAT) per VAT rate
• Applicable VAT rate(s)
• VAT amount in euros
• Total amount including VAT
• Date of delivery/performance (if different from the invoice date)
• Payment terms and IBAN
• Structured reference
• Situation-specific wording if applicable (reverse charge, exemption, export, etc.)
• Sent via Peppol (if Belgian B2B)

Conclusion

Invoice requirements in Belgium are not mere formalities: they determine the document's tax validity, your client's right to deduct VAT, and your own compliance in the event of an audit. In 2026, with mandatory electronic invoicing via Peppol coming into force, most of these details are handled automatically by your invoicing software, provided it is configured correctly.

Take the time to check that your invoicing software includes all the required details, and do not hesitate to ask your accountant to validate an invoice template before you start invoicing.

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This article was written by the Espero-Soft team for the blog dedicated to entrepreneurs in Belgium. For personalised advice, consult an ITAA-accredited accountant or FPS Finance.