Sending and receiving Peppol documents in Belgium for the companies you onboard

This guide walks through everything needed to exchange Peppol documents for a company registered in Belgium, assuming you are integrating Recommand into your own product and onboarding Belgian companies as your users, and that the company sends and receives documents over Peppol. Change any of the three answers at the top of the page to get the guide for a different situation.

What you are building

You are onboarding companies that are not your own: one Recommand team, and a company inside it for every customer you put on the network. Your customers never need a Recommand account — they see your interface, and Recommand stays behind your API calls.

That shape has a few consequences worth knowing before you write code:

• One team, many companies. There is no limit on companies per team, and billing is per team with the document volume of all companies pooled together, so the more companies you onboard the lower your price per document. See pricing per team.
• Every company is registered and verified individually. Peppol identifies companies, not platforms. Each company gets its own Peppol address and its own authorisation record.
• Verification is taken care of. Recommand hands you a URL that the company's authorised representative opens to confirm their identity. You present or forward that link; you never need to handle identity documents yourself. If you prefer to handle verification yourself, reach out to us at support@recommand.eu, we have a few other flows we can set up for you.
• You can run the whole flow under your own brand. The API is designed for white-label use, see can I whitelabel Recommand.

The Recommand dashboard shows the same teams, companies and documents your API calls produce, which is the quickest way to see what a customer is looking at while you are debugging.

Peppol in Belgium

Belgium runs on the standard European Peppol stack, which makes it the simplest of all countries to start in. Documents are exchanged as Peppol BIS 3 UBL, over the standard Peppol billing process, and Recommand's own access point and SMP handle both directions.

What is specific to Belgium:

• The B2B mandate is already in force. Since 1 January 2026 Belgian companies must be able to send and receive structured electronic invoices for domestic B2B transactions. See what if I don't switch to Peppol for what non-compliance means in practice.
• Enterprise numbers are the Peppol address. Belgian companies are published under scheme 0208 (enterprise number), which is why a Belgian Peppol address looks like 0208:0123456789. Sometimes, scheme 9925 is used as well, which is followed by a Belgian VAT number, like this: 9925:BE0123456789.
• Representatives are checked against the CBE. During verification, the name given for the representative is matched against the company's registered representatives in the Crossroads Bank for Enterprises, so a name that is not authorised is refused up front.

Create your team and API credentials

1. Sign up at app.recommand.eu/signup. The team you get is the container for every company you will onboard.
2. Create an API key on the API keys page. Note the key, the secret and your team ID.
3. Check the credentials with a request that needs no data of its own:

curl -X GET https://app.recommand.eu/api/v1/companies \
  -u key_xxx:secret_xxx

All endpoints in this guide live under https://app.recommand.eu/api/v1 and accept HTTP Basic authentication with the key as username and the secret as password. If you would rather not store a long-lived secret, JWT API keys and OAuth2 with a JWT assertion are available too, see the authentication guide.

Try it safely first

Build the whole flow against a playground team before you touch production. Playgrounds look and behave like production teams, but nothing is delivered over the real Peppol network, there are no SMP registrations, no subscription checks and no billing.

Create one from the team switcher at the top of the dashboard: Add playground, give it a name, and you are switched into it. There is no limit on how many you create.

Everything that follows in this guide is identical there: same endpoints, same validation, same webhooks (triggered by simulated inbound delivery). Register a company in the playground and use it as both sender and recipient to see a document arrive.

Three things worth knowing before you start:

• POST /:companyId/generate takes the same body as the send endpoint and returns the exact XML that sending would produce, fully validated, without transmitting, storing or billing it. It also returns the resolved documentType, doctypeId and processId, which is the quickest way to check that your country-specific fields map to the format and process you expect.
• Failure addresses. In a playground that is not connected to the Peppol Test Network, sending to 404:404 or 0208:1234567894 always fails, so you can exercise your error handling. Any other unregistered recipient is skipped without an error.
• The Peppol Test Network. For genuine end-to-end tests with real counterparties, tick Use Peppol Test Network when you create the playground. It then uses dedicated test access point and SMP endpoints while staying fully separated from production. The setting cannot be changed after creation, so make a second playground if you want both.

More detail in the getting started guide and how do I use the playground environment.

Register the company

Create one company per customer with the create company endpoint. Registration on the Peppol network happens as part of this call: identifiers and document types are set up for you, based on the company's country.

const auth =
  "Basic " + Buffer.from("key_xxx:secret_xxx").toString("base64");

const response = await fetch("https://app.recommand.eu/api/v1/companies", {
  method: "POST",
  headers: { Authorization: auth, "Content-Type": "application/json" },
  body: JSON.stringify(company),
});

const result = await response.json();
if (!result.success) throw new Error(JSON.stringify(result.errors));

const companyId = result.company.id;
const verificationUrl = result.verificationUrl; // hand this to your user

curl -X POST https://app.recommand.eu/api/v1/companies \
  -u key_xxx:secret_xxx \
  -H "Content-Type: application/json" \
  -d @company.json

The response carries a verificationUrl straight away. Keep it: the next step is to put it in front of the company's representative.

The exact identifier fields to send depend on the country, which is what the next section covers. If you would rather create identifiers and document types yourself instead of accepting the country defaults, pass skipDefaultCompanySetup: true and use the company identifiers and company document types endpoints.

Belgian identifiers and Peppol address

{
  "name": "ACME Corporation",
  "address": "123 Main Street",
  "postalCode": "1000",
  "city": "Brussels",
  "country": "BE",
  "enterpriseNumber": "0123456789",
  "enterpriseNumberScheme": "0208",
  "vatNumber": "BE0123456789"
}

Both numbers are validated against the national rules, including the modulo-97 check digit, and a mismatch is rejected instead of silently registered. For Belgian companies the enterprise number is derived from the VAT number when you leave it out.

Two Peppol identifiers are then registered for the company:

• 0208:0123456789 — the enterprise number, and the address others will use
• 9925:BE0123456789 — the VAT number

The company's Peppol address is the first one: 0208: followed by the enterprise number.

Registering for both directions

Sending needs no registration of its own; receiving does. So register the company as a recipient, which is the default:

{
  "isSmpRecipient": true
}

What that means:

• The company becomes findable on the Peppol network and can be delivered to through Recommand's access point, while sending its own documents out through the same access point.
• Recipient registration is exclusive. If the company already receives through another Peppol provider, registration fails until it is deregistered there. What that takes depends on the country, which the next section covers.
• The document types the company accepts are registered along with it, based on its country. Which ones those are is covered further down.
• The company is only published once it is verified.

Moving an existing Belgian registration

Since the B2B mandate came into force, most Belgian companies are already reachable over Peppol through a provider of their own. Recipient registration is exclusive, so registering the enterprise number under scheme 0208 fails while the company is still published somewhere else: it has to be deregistered at its current provider first.

If this is the case, we will let you know which SMP the company is published on. You can also look the enterprise number up ahead of time with the verify endpoint, which returns the same thing.

Verify the company

A company cannot exchange documents on Peppol until an authorised representative has confirmed their identity. The company object exposes this as isVerified, and it stays false until the check is done.

For Belgian companies the flow is short:

1. Open the verification URL (from the create-company response, the dashboard, or a fresh one from the verify company endpoint).
2. Fill in the representative's first and last name. That name is checked against the Crossroads Bank for Enterprises before the identity check starts: a name that matches none of the company's registered representatives is refused.
3. Complete the identity check. isVerified flips to true and the company is published on the Peppol network.

In some cases manual verification by our team will be required. If that's the case, isVerified will remain false until this manual verification is completed. The user is informed of this in the verification process.

Building verification into your onboarding

With one company you would click through this once. With many, verification is part of the flow you build: every company you register needs its own, and it is the step most likely to leave a customer stuck halfway.

Show the URL immediately. The create-company response already carries verificationUrl — no extra call needed. Put it in front of the user while they are still in your onboarding.

Ask for a fresh one when the moment has passed. Links get lost, and companies you created earlier never had one shown. The verify company endpoint starts a new verification session:

curl -X POST https://app.recommand.eu/api/v1/companies/{companyId}/verify \
  -u key_xxx:secret_xxx

The company.verification webhook fires when verification reaches a final state: verified, rejected or error. A company that comes back rejected or error and is not surfaced anywhere sits silently unusable. See working with webhooks.

Respect isVerified in your own UI. Do not let a user press send for a company that is not verified yet; this will result in an error. You should inform the user what is missing instead.

Re-verify after identifier changes. Updating a company's vatNumber or enterpriseNumber resets isVerified to false. Check the field after an update and present a new verificationUrl if it flipped.

The full mechanics are in the company verification guide.

The document format

For Belgium there is nothing to pick: leave the format alone and you send Peppol BIS 3 UBL, over the standard Peppol billing process. That is what Belgian recipients register, and what the Belgian B2B mandate expects.

Two things are still worth checking before a first send to a new recipient:

• Is the recipient on the network? The verify endpoint answers that, and sending performs the same check automatically.
• Does the recipient accept this document type? The verify document support endpoint answers that. Most Belgian recipients accept invoices and credit notes; not all accept every other type. This is also checked automatically when sending.

See verifying recipients for the full flow, including what to do when a recipient cannot be reached.

Send a document

One endpoint sends everything: POST /:companyId/send. The companyId is the sender, recipient is the Peppol address of the receiver, and document is the invoice or credit note as JSON. Recommand will validate the document and generate the XML.

const response = await fetch(
  `https://app.recommand.eu/api/v1/${companyId}/send`,
  {
    method: "POST",
    headers: { Authorization: auth, "Content-Type": "application/json" },
    // The body below, with doctypeId and countrySpecific where the country
    // needs them.
    body: JSON.stringify(sendRequest),
  }
);

const result = await response.json();
if (!result.success) {
  // result.errors is keyed by field path, e.g. { "buyer.vatNumber": [...] }
}

curl -X POST https://app.recommand.eu/api/v1/{companyId}/send \
  -u key_xxx:secret_xxx \
  -H "Content-Type: application/json" \
  -d @send-invoice.json

{
  "recipient": "0208:0123456789",
  "documentType": "invoice",
  "document": {
    "invoiceNumber": "INV-2026-001",
    "issueDate": "2026-08-17",
    "dueDate": "2026-09-16",
    "currency": "EUR",
    "buyer": {
      "name": "Customer Company",
      "street": "Customer Street 1",
      "city": "Antwerp",
      "postalZone": "2000",
      "country": "BE",
      "vatNumber": "BE0987654321"
    },
    "paymentMeans": [{ "iban": "BE68539007547034" }],
    "lines": [
      {
        "name": "Consulting Services",
        "quantity": "10.00",
        "unitCode": "HUR",
        "netPriceAmount": "100.00",
        "vat": { "category": "S", "percentage": "21.00" }
      }
    ]
  }
}

The seller block is filled in from the company when you leave it out, which is usually what you want: it keeps the company's registered identifiers and the document in agreement.

Things worth wiring up while you are here:

• Validation errors. Outgoing documents are always validated. A success: false response with errors keyed by field path is a document your recipient would have rejected, so surface it to the user who typed the data.
• Email fallback. Pass email.to with when: "on_peppol_failure" to fall back to email when a recipient turns out not to be reachable over Peppol, or send with recipient: null for email-only delivery. See email delivery and notifications.
• PDFs. pdfGeneration.enabled attaches a generated PDF of the document. You can also attach an existing PDF (or other files) via attachments; see adding attachments.

For a full field reference, see sending invoices and sending credit notes.

Document types registered for you

When you register a Belgian company as a recipient, it is published for the two document types that cover almost all Belgian traffic:

Anything sent to the company in one of these formats is accepted, validated, stored and handed to you. A sender who tries a document type the company is not published for gets an error before delivery, which is exactly the point of the registration.

Need more document types, such as self-billing, message level responses, invoice responses? Register the combinations you want with the create company document type endpoint.

Get incoming documents into your product

Recommand receives, validates and stores incoming documents for every company in your team. You pick them up in one of two ways.

Webhooks (recommended)

Register an endpoint once with the create webhook endpoint or through the dashboard and events are pushed to you as they happen, document.received among them:

await fetch("https://app.recommand.eu/api/v1/webhooks", {
  method: "POST",
  headers: { Authorization: auth, "Content-Type": "application/json" },
  body: JSON.stringify(webhook), // the body below
});

curl -X POST https://app.recommand.eu/api/v1/webhooks \
  -u key_xxx:secret_xxx \
  -H "Content-Type: application/json" \
  -d @create-webhook.json

{
  "url": "https://your-app.example/webhooks/recommand",
  "companyId": null,
  "secret": "your_webhook_signing_secret"
}

companyId: null covers every company in the team.

Pass a secret and verify the HMAC SHA-256 signature on every delivery before you trust the payload. Switch on event.eventType, and acknowledge with a 200 before doing the heavy processing. Both are covered in working with webhooks.

Polling the inbox

If you would rather pull, the inbox endpoint lists unread documents:

const inbox = await fetch("https://app.recommand.eu/api/v1/inbox", {
  headers: { Authorization: auth },
}).then((r) => r.json());

Mark each document as read with the mark as read endpoint once your system has it, so it drops off the list.

After you have the document

• Fetch details, the original XML or a rendered PDF from the documents endpoints.
• Route documents to the right customer with labels and suppliers, and automate that routing with rules.
• Let Recommand mail incoming documents on to an address of your choosing when that is easier than an API call, see email delivery and notifications.

For the full picture, including retries and idempotency, see receiving documents.

Going live

Before you switch your first real customer over, walk this list:

• A valid subscription in production. Playgrounds skip the subscription check; production does not.
• Verification handled in your UI. Show the verificationUrl at the right moment, make it forwardable, and handle the company.verification webhook so a company that comes back rejected or error does not sit silently unusable.
• isVerified respected. Do not let a user press send for a company that is not verified yet; explain what is missing instead.
• Webhook endpoint hardened. Signature verification, a fast 200, retries and idempotency on your side.
• Errors surfaced, not swallowed. Validation errors name the field that is wrong; put that in front of the person who can fix it.
• One real document, end to end. Send an invoice between two companies you control on production before letting customers in.

Where to get help

• Troubleshooting. Common rejections, delivery failures and validation errors are collected in the troubleshooting guide.
• Questions. The FAQ covers Peppol, addressing, VAT and billing.
• Email. support@recommand.eu:include the company ID and, for a delivery problem, the document ID.
• Discord. Join the server for release announcements and quick questions.
• Keep track of changes. New endpoints and behaviour are recorded in the changelog.

Other guides for Belgium

• Sending Peppol documents in Belgium for the companies you onboard
• Receiving Peppol documents in Belgium for the companies you onboard
• Sending Peppol documents in Belgium for your own company
• Receiving Peppol documents in Belgium for your own company
• Sending and receiving Peppol documents in Belgium for your own company