Chorus Pro is a mandatory service provided by the French government for invoicing French public institutions. Before a supplier can issue invoices through the platform, they need a Chorus Pro technical account and must be registered with Invopop using the Chorus Pro app.In this guide you’ll learn how to create the Chorus Pro credentials and register a supplier. Once a supplier is registered, continue with the companion guide: Chorus Pro issuing invoices.
{ "name": "Chorus Pro register supplier", "description": "Register a supplier with Chorus Pro", "schema": "org/party", "steps": [ { "id": "9ed27c40-4ced-11f0-bcdc-61b84b5eeae8", "name": "Set state", "provider": "silo.state", "summary": "Set state to `processing`{.state .processing}", "config": { "state": "processing" } }, { "id": "b8d3dc10-4ba3-11f0-a0a5-bbd7c9d8117a", "name": "Register supplier with Chorus Pro", "provider": "chorus-pro.register" }, { "id": "a3d43940-4ced-11f0-bcdc-61b84b5eeae8", "name": "Set state", "provider": "silo.state", "summary": "Set state to `registered`{.state .registered}", "config": { "state": "registered" } } ], "rescue": [ { "id": "a6c4f090-4ced-11f0-bcdc-61b84b5eeae8", "name": "Set state", "provider": "silo.state", "summary": "Set state to `error`{.state .error}", "config": { "state": "error" } } ]}
Before starting, review the workflows guide to understand the general setup process.In Console, create a new workflow and choose Empty Party workflow as the base. Name the workflow with a descriptive label such as “Chorus Pro Supplier Registration”.The new workflow performs a single step:
Register supplier with Chorus Pro
Add any additional steps you need such as error handling, and save the new workflow.
Keep the workflow ID at hand as you’ll need it later.
This section explains what suppliers need to configure within their Chorus Pro account to enable integration with Invopop.To configure Chorus Pro, complete these steps:
1
Create a Chorus Pro account
Sign up for a Chorus Pro account if you don’t have one.
To test in sandbox mode, create an account in the Chorus Pro sandbox. Download a CSV file with test accounts. Use one of the accounts to log in. For more information, visit the Chorus Pro documentation.
2
Navigate to API settings
Once logged in to your Chorus Pro account, navigate to the API configuration area:
Go to Domains > Connections in the main menu
Navigate to Domains → Connections
Click Access Service in the Technical Account section (bottom left)
Navigate to Technical Account
This opens a new page where you can manage your technical accounts.
3
Create a technical account
Set up the technical account credentials, this opens a form to create a technical account:
Set the type of request to Creation of a technical account
Select your company in the company field
This creates a login and password. Copy these credentials as you’ll need them when registering with Invopop
Now that you have a technical account, you can register a supplier with Chorus Pro.
1
Upload a Supplier
Use the Create an entry endpoint to upload a new supplier. Include a party object in the data field. For this step, you only need the VAT number.After successful upload, you’ll see the supplier in the Parties section with status Empty.
Supplier registration
2
Send the Supplier to the registration workflow
Send the supplier to the registration workflow using the Create a job endpoint. Use:
The supplier’s silo entry UUID from the previous step
The Supplier Registration workflow ID from the Setup section
This workflow generates a unique URL for the supplier to access and complete the registration process. The URL is stored in the supplier’s metadata.
3
Complete Chorus Pro Authentication
The workflow stays in progress until the supplier completes the registration process. The supplier must access the link and add the credentials they created previously.
The supplier’s status will change to Registered when authentication is complete.
You can fill the form via API by sending a PUT request to the registration link. The payload should be a JSON object with the following fields:
username (string): The supplier’s Chorus Pro username.
password (string): The supplier’s Chorus Pro password.
At this point, you’re ready to start sending invoices on behalf of the supplier. Head over to the Chorus Pro issuing invoices guide to continue.
For B2B PA flows: register the supplier via the France PA Register Party workflow (publishes the SIREN to the Annuaire and Peppol). For Chorus Pro: register the supplier with their SIRET on Chorus Pro’s portal and link credentials in the Chorus Pro app.
How are supplier credentials stored in Invopop for France?
France PA does not require supplier-side certificates — Peppol uses Invopop’s AP cert. Chorus Pro uses an OAuth token bound to the supplier’s account; the token is encrypted at rest in Invopop.
What happens if my supplier registration fails?
Ensure the supplier has a valid Chorus Pro account and provided correct credentials. Contact support if registration workflow issues persist.
What credentials does Chorus Pro require to authenticate a supplier?
OAuth 2.0 client credentials issued by Chorus Pro after registration. Invopop stores the token encrypted; suppliers can revoke access at any time through Chorus Pro’s portal.
How do I register for a Peppol inbox in Invopop?
Upload the company as a party (Console → Parties → Suppliers → + New Supplier, or via the Create an Entry API) with name, tax_id, address, and email. Then run it through the party registration workflow — the contact will receive a registration wizard link to provide proof of ownership.Once approved, the party is registered on the Peppol network (SMP+SML+Peppol visibility by default with the ubl-invoice doc group) and ready to receive invoices.
I get 'XXXX:XXXXXXXXX is already registered' when registering a supplier — what now?
A supplier with that Participant ID already exists in your workspace. Either reuse the existing party or, if it really is a new entity, check whether it should be registered under an alternative scheme (for example Belgium’s 9925 VAT scheme rather than the default 0208).
How do I assign multiple inboxes to a single supplier?
Register them through different silo entries, even though they represent the same legal party. The supplier must upload proof of ownership for each inbox.
What are Participant IDs?
Unique identifiers for entities on the Peppol network, made up of two parts:
Scheme — identifies the type of identifier (e.g. 9920 for Spanish VAT, 0208 for Belgian KBO/BCE)
Code — the actual identification number
Participant IDs are usually based on VAT numbers or local business identifiers, and Invopop can derive them automatically from a Tax ID. Some countries support multiple schemes — Belgium, for example, defaults to 0208 but some entities are only registered under 9925 (VAT). If you hit a “receiver not found” error, the recipient may be registered under an alternative scheme.
What visibility level should I set on my Peppol Party?
Peppol Party visibility determines what you can send and receive:
smp — SMP only, for testing
smp+sml — SMP and SML, useful when you only want to send
smp+sml+peppol — SMP, SML, and the Peppol Directory, recommended for both sending and receiving (and for being discoverable in the Directory)
