Belgium B2B e-invoicing: mandatory from 1 January 2026

From 1 January 2026, all Belgian VAT-registered businesses are required to send and receive structured e-invoices. The mandate applies to all businesses regardless of size.

Belgium requires e-invoices in PEPPOL BIS Billing 3.0 format, compliant with the European standard EN 16931. Invoices must be delivered via the PEPPOL network or the Mercurius platform.

Yes. Unlike some other EU countries that have phased rollouts by business size, Belgium's mandate applies to all VAT-registered businesses from day one. There are no size-based exemptions.

Not for B2B transactions involving Belgian VAT-registered businesses. Structured e-invoices in PEPPOL BIS 3.0 format are required. PDFs may still be acceptable for B2C or cross-border transactions not subject to Belgian VAT.

Yes. Invoicia generates PEPPOL BIS Billing 3.0 XML, which is the required format. Pro plan enables direct PEPPOL network sending through an Access Point provider.

Mercurius is the Belgian government's e-invoicing platform, originally built for public-sector (B2G) invoicing. For the B2B mandate, businesses can deliver structured invoices via either the PEPPOL network or Mercurius directly. In practice, most accounting software connects through a certified PEPPOL Access Point, which automatically routes to Mercurius for government recipients. Invoicia Pro uses a certified Access Point for direct PEPPOL delivery.

Yes. The PEPPOL network uses the AS4 messaging protocol for machine-to-machine e-invoice delivery — this is the de-facto Belgium e-invoicing API for software integrations. ERP and accounting systems connect through a certified PEPPOL Access Point that handles the AS4 protocol. Invoicia's Pro plan includes Access Point connectivity, so no direct API integration is needed on your side.

No. The B2B mandate only covers transactions between VAT-registered businesses. B2C invoices — issued to private consumers — are not required to be structured e-invoices under the 2026 Belgian law. If you issue both B2B and B2C invoices, only your B2B transactions require PEPPOL BIS 3.0 delivery via Mercurius e-invoicing or a PEPPOL Access Point. Belgium also has a separate B2G (business-to-government) requirement via Mercurius, in force since 2020.

If you are a foreign company with a Belgian VAT registration that issues B2B invoices to other Belgian VAT-registered businesses, you are within scope of the 2026 mandate and must send PEPPOL BIS 3.0 e-invoices. If you are a foreign company without a Belgian VAT number invoicing Belgian customers across borders, you are not obligated under Belgian law — but your Belgian customers may still require PEPPOL delivery as their preferred channel for reception. PEPPOL BIS Billing 3.0 is the de-facto cross-border EU standard, so issuing in this format is the safest option. Invoicia generates compliant XML on the free plan and routes it via the PEPPOL network on Pro.

Belgium's tax authority (FOD Financiën / SPF Finances) is taking a graduated enforcement approach. Initial fines for failure to issue PEPPOL BIS 3.0 invoices to Belgian B2B customers start at EUR 1,500 per infraction for repeat offences and can escalate substantially with continued non-compliance. The bigger commercial risk is practical: customers cannot deduct input VAT from invoices that don't meet the structured-format requirement, so non-compliant suppliers risk losing business. Switching to a PEPPOL-capable platform like Invoicia avoids both the regulatory and commercial exposure.

You don't register directly on PEPPOL — registration happens via a certified PEPPOL Access Point. The Access Point publishes your company's PEPPOL participant ID (typically your Belgian VAT number with the 9925 country prefix) to the PEPPOL SML/SMP directory, which makes you discoverable by all other PEPPOL users. With Invoicia Pro, registration on PEPPOL is handled automatically when you upgrade — no manual setup or technical PEPPOL integration is required. Once registered, you can both send and receive PEPPOL BIS Billing 3.0 invoices.

PEPPOL and Mercurius are two delivery channels for the same structured invoice format (PEPPOL BIS Billing 3.0). PEPPOL is the European four-corner network used between businesses: your accounting software sends the invoice through a certified Access Point, which routes it to the recipient's Access Point. Mercurius is the Belgian government's e-invoicing platform, primarily used for B2G (public-sector recipients) but also accessible for B2B. In practice, most Belgian B2B invoicing flows through PEPPOL; Mercurius is the route to government entities. Invoicia's Pro plan uses a certified PEPPOL Access Point, which automatically routes to Mercurius when the recipient is a Belgian public-sector body — so you don't have to choose manually.

Belgian companies use ICD scheme 0208 (their Belgian enterprise number / KBO-BCE number) or 9925 (with the Belgian VAT prefix BE followed by 10 digits). For example, a Belgian VAT number BE0123456789 becomes the PEPPOL participant ID 9925:BE0123456789 — this is the address other PEPPOL users send invoices to. Invoicia automatically builds the correct participant ID when you enter a Belgian VAT number, and looks up the recipient's PEPPOL endpoint to confirm they can receive structured invoices before sending.

Yes. If you are self-employed in Belgium and registered for VAT (BTW/TVA), the 2026 B2B e-invoicing obligation applies to you exactly as it does to incorporated businesses. There is no exemption for size, legal form, or revenue. Self-employed professionals invoicing other VAT-registered Belgian businesses must issue PEPPOL BIS Billing 3.0 invoices via the PEPPOL network or Mercurius. Invoices to private consumers (B2C) remain exempt. Invoicia's free plan generates compliant PEPPOL XML for up to 20 invoices per month — enough for many freelancers — and Pro adds direct PEPPOL network delivery.