Self-Billing via Peppol with Flexina

Self-billing (also called self-invoicing or buyer-created invoicing) via Peppol automates supplier flows without PDF or manual entry. With Flexina, receiving self-invoices is included in purchase management, and a new emission module is available.

Self-billing, self-invoicing, buyer-created invoice: what does it mean?

Self-billing refers to self-invoicing: the customer generates the invoice on behalf of the supplier. This is also known as buyer-created invoicing or reverse billing. Typical use cases:

• commissions and royalties
• recurring services
• framework contracts with suppliers
• purchasing centers and groups

How does self-billing differ from regular invoicing?

In a standard invoicing process, the supplier issues the invoice to their customer. The supplier determines the amounts, applies the appropriate VAT rate, and sends the document to the customer for payment. The customer receives the invoice, verifies it, and proceeds with payment.

With self-billing, this flow is reversed. The customer takes responsibility for issuing the invoice on behalf of the supplier. The customer knows the services performed or goods delivered, calculates the amounts due, and issues the invoice bearing the supplier's details. The supplier then receives this self-invoice and simply needs to validate it.

This reversal of the invoicing flow offers a major advantage: the customer controls the invoicing timeline and ensures consistency between purchase orders, delivery notes, and invoices. Discrepancies and disputes are significantly reduced since the same party holds the information about services received and creates the billing document.

Legal requirements for self-billing in Belgium

Self-billing is explicitly provided for in Belgian VAT legislation. Article 53 §2, paragraph 2 of the VAT Code establishes this practice and defines the substantive conditions. Article 5 of Royal Decree No. 1 of 29 December 1992 specifies the mandatory mentions that must appear on every invoice, including self-invoices. Circular AAFisc No. 53/2013 from FPS Finance details the implementation terms. To be valid in Belgium, self-billing must meet several conditions.

Prior agreement between the parties

A prior agreement (or self-billing agreement) must be concluded between the customer and supplier before self-billing operations begin. Since Circular AAFisc No. 53/2013, the form of this agreement is free: it may be verbal or written, at the parties' discretion. However, a written agreement is strongly recommended as proof of the agreement's existence must be available upon request from the tax authorities. This agreement must specify the conditions under which the customer will issue invoices on behalf of the supplier, including the parties involved, the nature of the transactions covered, the procedure for the supplier to accept invoices, and the duration of the agreement.

Supplier acceptance procedure

The supplier must have a formal acceptance procedure for each self-invoice issued in their name. This acceptance can be explicit (express validation of each invoice) or tacit (absence of dispute within an agreed timeframe). The self-billing agreement must specify which mechanism applies.

Mandatory mentions

Each self-invoice must include the mention "Self-billing" (or "Autofacturation" in a Belgian context). This clearly indicates that the invoice was issued by the customer, not the supplier. All other mandatory invoice mentions remain applicable: VAT numbers of both parties, description of goods or services, amounts excluding VAT, VAT rate and amount, and total amount including VAT.

Sequential numbering

Self-invoices must follow a sequential numbering system allowing each document to be uniquely identified. In practice, it is recommended to use a numbering series that is separate from regular sales invoices, to avoid confusion in the supplier's sales journal. This numbering sequence must be continuous and without gaps.

When is self-billing commonly used? Typical scenarios

Self-billing is particularly suited to situations where the customer holds all the information needed to issue the invoice and where transaction volumes justify process automation.

Subcontractors and freelancers

Companies working with numerous subcontractors or freelancers frequently use self-billing. The principal knows precisely the hours worked, the agreed rates, and the validated deliverables. Rather than waiting for each contractor's invoice (with potential delays and errors), they issue the self-invoice directly. This approach is particularly common in consulting, IT, temporary staffing, and construction sectors.

Commissions and royalties

Commission and royalty agreements are a natural fit for self-billing. The customer (principal or licensee) knows the turnover generated and can precisely calculate the commissions or royalties due. Self-billing avoids disputes over calculation bases and accelerates payments.

Recurring services with variable pricing

When services are provided on a recurring basis but with variable amounts (for example based on consumption or volumes), self-billing allows the customer to automatically generate invoices based on actual data recorded in their system.

Purchasing centers and retail

Purchasing centers and large retailers use self-billing extensively with their suppliers. Transaction volumes are such that automation is essential. The retailer issues self-invoices based on deliveries received and prices agreed in framework contracts.

Platforms and marketplaces

Digital platforms that remunerate third-party sellers or service providers use self-billing to efficiently manage financial flows with hundreds or thousands of partners. The platform automatically issues self-invoices based on transactions recorded in its system.

Electronic self-billing via Peppol: what are the benefits?

In electronic Peppol format, the self-invoice is:

• structured in UBL format (readable by accounting software)
• transmitted via the Peppol network (secure European standard)
• fully automatable (zero manual entry, zero errors)
• compliant with Belgian electronic invoicing requirements

Result: no more PDF self-invoices by email and no time-consuming manual entry.

How does electronic self-billing work via Peppol?

The Peppol network (originally Pan-European Public Procurement OnLine, now a standalone brand name) is a secure communication infrastructure that enables the exchange of structured business documents between companies across Europe and beyond. Here is how self-billing integrates into this ecosystem.

The customer (self-invoice issuer) uses their management software connected to a Peppol Access Point. When they generate a self-invoice, the document is automatically converted to UBL 2.1 (Universal Business Language) format, the standard used by the Peppol network. In Peppol BIS Self-Billing 3.0, the self-invoice uses invoice type code 389 (instead of 380 for a standard invoice), identifying it as a buyer-created invoice. This structured document contains all required information: the supplier's Peppol identifier, amounts, VAT, self-billing mention, and agreement references.

The UBL document is then transmitted via the Peppol network to the supplier's access point. The supplier receives the self-invoice directly in their accounting or management software, without any manual intervention. The supplier can then verify and accept it according to the procedure agreed in the self-billing agreement.

The fundamental advantage of Peppol for self-billing is standardization. The UBL format ensures that all information is present, correctly structured, and directly usable by both parties' IT systems. There is no longer any risk of data loss, data entry errors, or incompatible formats.

Setting up self-billing: step by step

Implementing a self-billing process via Peppol follows a structured path with several steps.

1. Identify eligible suppliers

Start by identifying suppliers for whom self-billing makes sense. Prioritize relationships with high transaction volumes, contracts with predefined pricing, and suppliers that already have a Peppol identifier.

2. Draft the self-billing agreement

Establish an agreement with each relevant supplier. While the form is free, a written agreement is strongly recommended. This agreement must specify the self-billing terms: scope of operations covered, issuing frequency, acceptance procedure (tacit or express), dispute timeframe, and duration of the agreement.

3. Configure the management software

Set up your management solution to activate self-billing with selected suppliers. In Flexina, this involves activating the self-invoice emission module, entering supplier data (VAT number, Peppol identifier, agreed conditions), and configuring the dedicated sequential numbering.

4. Test the process

Before going live, conduct tests with one or two pilot suppliers. Verify that self-invoices are correctly generated, transmitted via Peppol, and properly received by the supplier. Validate amounts, VAT, and legal mentions.

5. Deploy and monitor

Once tests are validated, roll out self-billing progressively with all relevant suppliers. Set up regular monitoring to check acceptance rates, identify any disputes, and optimize the process.

VAT implications of self-billing in Belgium

Self-billing has direct VAT implications that must be properly managed.

VAT deduction

The self-invoice issued by the customer constitutes a valid document for VAT deduction, provided it includes all mandatory mentions and the self-billing agreement is in order. The customer can exercise their right to deduction based on the self-invoice they themselves issued.

Supplier VAT return

On the supplier's side, the accepted self-invoice (expressly or tacitly) constitutes the reference invoice for their VAT return. The supplier must include the VAT amounts from the self-invoice in their periodic return, even though they did not issue the document.

Reverse charge and self-billing

It is important not to confuse self-billing with the reverse charge mechanism. The reverse charge is a mechanism whereby the purchaser of goods or services is liable for VAT instead of the supplier. Self-billing, on the other hand, concerns only the invoice issuance process, not who is liable for VAT. However, both mechanisms can be combined in certain situations, particularly for intra-community service supplies.

Notification to the VAT control office

Each party must inform their VAT control office of the self-billing arrangement. The customer informs their office that they have opted for self-billing, while the supplier communicates the identity of all customers using this system.

Client listing and intra-community reporting

Self-billing transactions must be properly reported in the annual client listing and, where applicable, in the intra-community statement. The supplier must declare received self-invoices as sales, while the customer includes them in their purchases.

Receive self-billing invoices via Peppol with Flexina: with the purchase management module

With Flexina, you can receive self-billing invoices (self-invoicing) via Peppol with the purchase management module: it's included in the purchase management module.

The self-invoice received via Peppol is treated as a standard purchase flow: clear tracking, simplified accounting.

New Flexina module: issue self-invoices via Peppol

Some companies want to go further and issue self-invoicing invoices themselves on behalf of their suppliers. This is particularly the case for:

• platforms and marketplaces
• purchasing organizations
• large accounts and groups
• companies with self-billing contracts

How Flexina handles electronic self-billing

Flexina integrates self-billing into its business management ecosystem. On the emission side, the module allows you to create self-invoices and send them in UBL format via Peppol to the supplier's access point, with the required "Self-billing" mention and invoice type code 389.

On the reception side, when a customer issues a self-invoice to you via Peppol, Flexina receives it in the purchase module like any other supplier invoice. The document is linked to the correct supplier and the invoice is ready for validation and posting.

Contact us to learn more about the detailed features of the self-billing module and integration possibilities with your existing processes.

Benefits of automating self-billing through Peppol

Automating self-billing via Peppol delivers measurable benefits at multiple levels.

Significant time savings

Eliminating manual entry and PDF document processing represents a significant time saving for companies handling a large volume of self-invoices.

Error reduction

Structured UBL data eliminates transcription errors, incorrect amounts, and missing legal mentions. Automated processing significantly reduces the error rate compared to manual processing.

Faster payments

Since the customer issues the invoice themselves, there is no longer a waiting period for receiving the supplier document. The self-invoice is immediately integrated into the payment workflow, which reduces settlement times and improves the commercial relationship with suppliers.

Guaranteed compliance

With mandatory electronic invoicing in Belgium, self-billing via Peppol guarantees full compliance. Documents are structured according to European standards, transmitted through a secure channel, and archived with complete traceability.

Scalability

The automated approach allows you to manage a growing volume of self-invoices without proportionally increasing administrative resources. Whether you process 50 or 5,000 self-invoices per month, the process remains identical and controlled.

Flexina and Peppol self-billing

Flexina allows you to manage self-billing in your invoicing:

• Reception via Peppol: with the purchase management module, receive self-billing invoices from your clients directly via the Peppol network.
• VAT rate configuration: set up your VAT rates and mandatory mentions, including the required "Self-billing" mention.
• Peppol correspondence: invoices exchanged via Peppol follow the structured UBL format with the VAT codes you have configured.

For more details on managing self-billing with Flexina, contact our team.

For which companies is self-billing via Peppol relevant?

• companies receiving self-invoices (commissions, recurring services)
• platforms working with many suppliers
• purchasing organizations and multi-entity organizations
• companies wanting to industrialize their self-invoicing process
• Belgian companies that need to comply with mandatory electronic invoicing

Frequently asked questions and common pitfalls

Is an agreement required for each supplier?

Yes. Belgian legislation requires a separate prior agreement for each supplier with whom you practice self-billing. This agreement must be concluded before the first self-invoice is issued. Since Circular AAFisc No. 53/2013, the form of the agreement is free (it may be verbal), but a written agreement is strongly recommended to prove its existence during a tax audit. Without this agreement, self-invoices are not legally valid and the right to VAT deduction may be challenged.

Can the supplier refuse a self-invoice?

Yes. The supplier retains the right to contest any self-invoice they consider incorrect. The dispute procedure and deadlines must be defined in the agreement. If refused, the self-invoice is cancelled and a credit note or new invoice must be issued.

Does the supplier need to issue an invoice in parallel?

No. When a self-billing agreement is in place, the supplier must not issue an invoice for the same transactions. The self-invoice issued by the customer is the only valid billing document. Double invoicing would create a double VAT liability and accounting complications.

Does self-billing work for intra-community transactions?

Yes, self-billing can be used for intra-community transactions. The Peppol network is specifically designed to facilitate cross-border exchanges within the European Union. The applicable VAT rules (reverse charge, zero rate) must be correctly reflected in the self-invoice.

What are the common pitfalls?

The most frequent errors are the absence of a written agreement, forgetting the "Self-billing" mention on the document, using a common numbering system with regular sales invoices, and failure to track supplier acceptances. With software like Flexina, these risks are eliminated through automatic checks and predefined settings.