What is Peppol? How e-invoicing works in Belgium

Peppol is the network Belgian businesses use to exchange structured e-invoices. Since 1 January 2026 it is required for B2B. How it works and how to connect.

By Artem Kuznetsov, founder

Published: 22 October 2026
Verified: 22 October 2026

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What matters now

Effective now: Structured e-invoices, by default Peppol BIS over the Peppol network, required between businesses established in Belgium since 1 January 2026. No tolerance period remains.
Next change: 1 January 2028 (planned): e-reporting of invoice data to the tax administration. Approved as a preliminary draft on 18 July 2026, not yet law.
Main impact: A PDF no longer meets the obligation between Belgian businesses. Lacking the means to send and receive costs €1,500, then €3,000, then €5,000.
Action today: Search 0208 plus your enterprise number on Peppol Lookup, then send one live invoice and receive one.

Sources

Peppol is the network Belgian businesses use to send each other invoices as structured data rather than as PDFs. Since 1 January 2026, an invoice from one Belgian VAT-registered business to another has to travel that way. You connect once, through invoicing or accounting software that is linked to the network, and your clients find you under your enterprise number.

Peppol is not a programme you install, and it is not a government website you log in to. It works more like the phone network: many providers, one set of rules, and anyone connected can reach anyone else who is connected.

What is Peppol?

Peppol is an international network and a set of agreements for exchanging business documents, such as invoices and credit notes, between companies and public bodies. It started in European public procurement and is now used well beyond it.

Nobody connects to Peppol directly. You connect through a certified Peppol service provider, also called an access point. In practice that is usually your invoicing or accounting software, which either is an access point or works with one.

How does an invoice travel over Peppol?

Peppol uses what is called the four-corner model:

You create the invoice in your software.
Your access point sends it over the network.
Your client's access point receives it.
Your client's software shows it, ready to book.

You and your client do not need the same provider. That is the point of the network: you choose your software, your client chooses theirs, and the invoice still arrives.

What is a Peppol ID?

Your Peppol ID is the number that identifies you on the network, a bit like a phone number. In Belgium, every business is registered at least under its enterprise number (KBO/BCE), with the prefix 0208. For the enterprise number 0308.357.159, the Peppol ID is 0208:0308357159.

Because that convention is fixed, you do not need to ask clients for their Peppol ID. If you know their enterprise number, your software can find them.

What is a Peppol invoice, and why is a PDF not one?

A Peppol invoice is a file in a fixed structure (Peppol BIS Billing 3.0, written in a format called UBL) that software can read field by field: who, what, how much, which VAT rate, which due date. Your client's software does not have to retype anything.

A PDF sent by email is a picture of an invoice. However tidy it looks, for an invoice that falls under the obligation it does not count as a structured invoice. A readable PDF may travel with the Peppol invoice as an attachment, but the structured file is the invoice.

Who has to send and receive Peppol invoices in Belgium?

Since 1 January 2026:

You must send structured invoices if you are a taxable person established in Belgium and you invoice another business that has to give you its Belgian VAT number. That includes businesses under the small-enterprise VAT exemption.
You must be able to receive them if you have a Belgian VAT number and buy from Belgian suppliers, even if you only sell to consumers.
No structured invoice is required for sales to private individuals, under the flat-rate scheme, for activities exempt from VAT under article 44 of the VAT Code, or, since 20 February 2026, for clients that are not established in Belgium.

The grace period is over. The general tolerance ended on 31 March 2026, and a narrower one for self-billing ended on 30 June 2026.

Is there a free government option, such as Hermes or Mercurius?

Not for invoices between businesses.

Hermes was a free federal service that received Peppol invoices for businesses that could not process them yet, turned them into a PDF and forwarded them by email. It was switched off on 31 December 2025, with read-only access to old invoices until March 2026.
Mercurius is the platform through which Belgian public authorities receive e-invoices. It is for invoicing the government, not other businesses.

FPS Finance chose not to build a central application for business invoices and leaves it to the market. Its own answer is that meeting the obligation can cost nothing when it comes with something you already pay for, such as accounting software or a bank account.

How do I get connected to Peppol?

Choose software that sends and receives over Peppol. FPS Finance publishes a list of compliant software but recommends none of them. Check that receiving is included, not only sending.
Let the provider register you. Registration happens through the provider, under your enterprise number (0208). If you were registered years ago under an older identifier based on your VAT number, ask which one you are on.
Check that you can be found. Search for 0208 followed by your enterprise number on Peppol Lookup (lookup.peppol.org). If you appear, others can send to you. The tool only shows that you can receive, not that you can send.
Test both directions. Send one real invoice and confirm it arrived. Ask a supplier to send you one, and confirm it reached your books.

The setup checklist goes through each step in more detail.

What if my client is not on Peppol?

Look them up first, with 0208 and their enterprise number. Most software does this for you before it sends.

If a client in scope really cannot receive a structured invoice for technical reasons, the law has allowed you since 20 February 2026 to send an ordinary invoice instead. You still have to invoice: send a PDF or paper invoice. If you send it electronically, your client has to agree to that channel. According to FPS Finance, that invoice is legally valid and you have met your invoicing obligation; the client is the one taking the risk. Once the client is connected, you do not have to send the old invoices again over Peppol.

Keep a note of the check: the date, and that your client did not appear on the network. If your client says they are connected but your invoice does not arrive, the troubleshooting guide walks through the usual causes.

What does it cost not to be ready?

The fine is for not having the means to send and receive structured invoices: €1,500 the first time, €3,000 the second, €5,000 after that. A finding only counts as a repeat if it comes at least three months after the previous one.

Receiving is the half that is easiest to miss. What a supplier PDF means for your VAT deduction is covered in the briefing on receiving, and every article behind the rules is in the legal reference. The next step, reporting invoice data to the tax administration, is planned for 2028 and has its own briefing.

Art. 53, § 2bis of the VAT Code (law of 6 February 2024) has required structured electronic invoices between taxable persons established in Belgium since 1 January 2026. Art. 13ter of Royal Decree no. 1 makes Peppol BIS in the UBL version, sent over the Peppol network, the default. Lacking the technical means to issue and receive costs €1,500, then €3,000, then €5,000.

Which instruments create the obligation?

Instrument	What it does
Law of 6 February 2024 (numac 2024001635)	Inserts art. 53, § 2bis VAT Code: the duty to issue, and the recipient's duty to be able to receive
Royal Decree of 8 July 2025 (numac 2025005169)	Art. 13ter and 13quater RD no. 1 (format and network); adds the fine to RD no. 44. In force 1 January 2026
Law of 10 February 2026 (numac 2026001291)	Art. 4: the technically-unable carve-out; narrows the scope to customers established in Belgium

How is the Peppol network organised?

Three roles. Participants (end users) send and receive. Service providers run the access points, the entry and exit points of the network, and the registers (SML/SMP) that publish where each participant's documents must go. Peppol Authorities sign the agreements with service providers and supervise correct use in their jurisdiction; OpenPeppol AISBL holds the framework together.

Exchange follows the four-corner model: sender, sender's access point, recipient's access point, recipient. Sender and recipient need not share a provider.

BOSA has been the Belgian Peppol Authority since 1 January 2016. According to BOSA, FPS Finance takes over that role from 2027.

How is a Belgian participant identified?

By the enterprise number under scheme ID 0208: 0208:[KBO number], for example 0208:0308357159 for FPS Finance. Service providers are contractually bound to register Belgian participants at least under that identifier (Peppol Authority Specific Requirements). Other identifiers (VAT number, GLN, IBAN) may be added by agreement, not instead of it.

Clients therefore do not need to be asked for a Peppol ID. Older registrations under a VAT-number-based identifier still exist; check which one a client sits on when an invoice will not route.

What format does the law require?

The law itself sets no format. Art. 13ter RD no. 1 requires conformity with the European standard and its syntaxes under Directive 2014/55/EU, as given concrete form in Peppol BIS in the UBL version (Peppol BIS Billing 3.0, an implementation of EN 16931), transmitted over the Peppol network.

The parties may agree on another format meeting the European standard (art. 13ter, second paragraph), but art. 13quater then requires the issuer to keep the means to issue and receive over Peppol anyway. A credit note that refers to a structured invoice is itself a structured invoice and is issued in the same format.

Two practical points from the FPS Finance FAQ: attachments travel in the same channel as the invoice, not by separate email; and the recipient keeps the structured invoice for the full retention period, with a readable form whose content cannot be altered.

Who is in scope?

Situation	Structured invoice required?
Established in Belgium, B2B with a customer established in Belgium	Yes
Small-enterprise exemption (art. 56bis)	Yes
Flat-rate scheme (art. 56)	No
Supplies exempt under art. 44	No
Bankrupt taxable person, for that activity	No
Customer not established in Belgium (since 20 February 2026)	No
Private individuals (B2C)	No

The recipient's duty follows from art. 53, § 2bis: a recipient identified for VAT under art. 50, § 1, first paragraph, 1° or 3° must be able to receive. A business that only sells to consumers but buys from Belgian suppliers still needs to receive. The receiving side, and what an unstructured supplier invoice means for deduction, is in the receiving briefing.

Tolerance: the general one ended on 31 March 2026; the targeted self-billing tolerance ended on 30 June 2026. Since then, fines are waived only after an individual review in exceptional technical cases.

What became of Hermes, and what is Mercurius?

Hermes, the free federal platform that received Peppol BIS invoices for Belgian businesses not yet able to process them, converted them to PDF and forwarded them by email, was decommissioned on 31 December 2025, with read-only access until March 2026 (minutes of the 37th Belgian Peppol service providers plenary, 30 September 2025). One older page on the e-invoicing portal still presents Hermes as available; it has not been updated.

Mercurius is the federal B2G platform: it receives e-invoices addressed to Belgian contracting authorities over Peppol, and offers a portal where a supplier can enter a simple invoice. B2G falls under the separate procurement framework (law of 17 June 2016) and is not what changed in 2026.

There is no government B2B solution. FPS Finance explained in May 2025 that it deliberately chose a decentralised, market-based approach, and that the cost of compliance can be zero when it is included in the base price of accounting software or a bank account.

How do I check whether a client can receive?

Peppol Lookup (lookup.peppol.org), searching on 0208:[KBO number] or by name. It shows that a participant can receive, not that it can send. Under the network's rules, publication in the directory counts as agreement to receive structured invoices.

What if the recipient cannot receive?

Art. 4 of the law of 10 February 2026 adds a paragraph to art. 53, § 2bis: the issuer need not issue a structured invoice where the recipient is unable, for technical reasons, to receive it. The issuer remains bound to issue an ordinary invoice under § 2.

The FPS Finance FAQ adds: an invoice sent by an alternative channel is legally valid and the sender has met its invoicing obligation; an electronic alternative requires the customer's agreement; the customer bears the risk of the fine; and no structured invoices need be sent retroactively once the customer is connected. Keep evidence of the lookup with the file.

What are the fines?

Annex to RD no. 44, section C, inserted by the RD of 8 July 2025: not having the technical means to issue and receive structured invoices costs €1,500 for a first infringement, €3,000 for a second, €5,000 thereafter. A finding counts as a second or subsequent infringement only if the administration establishes it at least three months after the previous one. Per-invoice fines for late or irregular invoices are separate; the legal reference has the full table.

For the file

Confirm each client sends and receives over Peppol, and record the identifier they are registered under.
Keep Lookup evidence for every in-scope customer invoiced outside Peppol.
Track supplier PDFs from Belgian suppliers; they point to a gap on one side.
Note the next change: transaction-level e-reporting, planned for 1 January 2028 and not yet law. For setup steps, the checklist; for routing failures, the troubleshooting guide.

DOKUS

Dokus sends and receives invoices over Peppol. Free is €0 with Peppol sending and receiving included without a monthly cap (fair use).

See how it works