Peppol E-Invoicing in Belgium: A Setup and Stabilisation Checklist for Freelancers

Structured e-invoicing has been mandatory for domestic B2B transactions between Belgian businesses since 1 January 2026. The general tolerance ended on 31 March 2026; a narrower one for self-billing ended on 30 June 2026. If you are asking whether Peppol is verplicht in Belgium in 2026: for in-scope invoices, yes, and it is already in force.

This guide is a practical checklist: what to set up, how to prove it works, and how to keep it working. Three other briefings go deeper:

• the legal reference, with the article behind each rule, the fines and the exceptions;
• the receiving side, which is its own obligation and where most setups fail silently;
• the troubleshooting guide, for an invoice your client says never arrived.

Structured invoicing and Peppol are not the same thing

The law requires a structured electronic invoice: one that conforms to the European standard for e-invoicing, as given concrete form in Peppol BIS in the UBL version. The Royal Decree names the Peppol network as the default way to exchange it.

Two consequences follow:

• A PDF sent by email is not a structured invoice, however it looks. For an in-scope transaction it does not satisfy the obligation.
• Peppol is the default, not the only option: the parties may agree on another format that meets the European standard. But anyone who does must still keep the technical means to issue and receive over Peppol.

Scope, in short

• In scope: a taxable person established in Belgium, invoicing a customer that must give a Belgian VAT number. This includes businesses under the small-enterprise VAT exemption.
• Not in scope: the flat-rate scheme, supplies exempt under art. 44 of the VAT Code, and sales to private individuals.
• Since 20 February 2026: you need not issue a structured invoice when the customer is technically unable to receive one. That is a narrow statutory exception, not a general excuse.
• Cross-border invoices follow other rules. Invoices to public authorities fall under a separate procurement framework that already applied before 2026.

The legal reference has the full table with the article for each line.

The setup checklist

1. Know your identifier

A Belgian participant is addressed with scheme 0208 plus the enterprise number. Some businesses were registered years ago under an older VAT-number-based identifier. Ask your provider which identifier you are registered under, and make sure it is the one your clients will look up.

2. Sending

• Your invoicing tool must produce Peppol BIS invoices and send them over the network.
• Keep your clients' enterprise numbers correct in your customer records. A wrong number means an invoice addressed to nobody.
• Before sending, check whether the client can be reached on Peppol. If it cannot, keep a record of that: it is what the technically-unable exception rests on.

3. Receiving

Receiving is a separate registration, and the fine for lacking the means covers receiving as well as sending.

• Forwarding an email inbox to a tool is not Peppol receiving. Receiving means your identifier is registered on the network with a provider that delivers invoices to you.
• If you change provider, the registration moves with you only when it is transferred. Until then, invoices keep going to the old one.
• Supplier PDFs that keep arriving from Belgian suppliers are a signal worth asking about: either the supplier is not ready, or they cannot reach you.

4. Prove both directions with a live test

• Send one real invoice to a Belgian B2B client and confirm it arrived.
• Have someone send you one real invoice on your identifier, and confirm it landed where your books are kept.
• Test a credit note, and any VAT case you use often.

A screen saying no error occurred is not a test. Delivery to the client's access point, and the client actually seeing the invoice, are different things; the troubleshooting guide walks through each.

5. Agree roles with your accountant

• Who sends final invoices?
• Who watches for undelivered or rejected invoices, and how often?
• Who follows up supplier PDFs?
• Who keeps the archive?

Keeping it stable

Once it works, the job is to notice when it stops working:

• Weekly: look at undelivered or rejected invoices, and close the cause rather than resending blindly.
• When a client changes: a new enterprise number, a merger or a new invoicing tool on their side can change where invoices must go.
• Monthly: list supplier invoices that came in as PDF from Belgian suppliers, and ask why.
• When you change tools: plan the transfer of your receiving registration before you switch.

What the fines are

The fine for not having the means to issue and receive structured invoices is €1,500 for a first finding, then €3,000, then €5,000. Separate per-invoice fines apply to invoices not issued on time. A later infringement only counts as a repeat once the administration has established it at least three months after the previous one. The legal reference sets out each amount with its source.

Where Dokus fits

Dokus creates invoices with official numbering and sends a confirmed invoice over Peppol, on every plan. It shows the state of each invoice after sending, so an undelivered invoice is visible instead of silent. Your accountant can be given access at no cost. See how sending works.