When we talk about e-invoicing flows, we often use corner models to show how documents move between different parties. The idea is the same everywhere: an invoice or another business document needs to be sent from the sender to the receiver.
The setup can vary from country to country. Some national systems use the Peppol flow as it is, while others adapt it and integrate Peppol into their own local model.
In this blog, we focus on Peppol, which is used in many countries to make cross-border and domestic trade easier. This article explains the Peppol network, focusing on the two main flows you might come across when dealing with e-invoicing: the Peppol 4-Corner Model and the Peppol 5-Corner Model.
Peppol 4-Corner Model
The 4-Corner Model is essentially the basic Peppol flow. It is the standard approach in many countries and is designed to make sure business documents are exchanged securely and reliably. In this setup, the document is sent from one Peppol Access Point to another, with each party connected to their own certified provider in the Peppol network.
Because both the sender and receiver can choose their own Access Point, the model provides flexibility while still ensuring compatibility across the network. In the table below, you can see more details about what happens at each corner.
| Corner | Role | What happens here |
| 1 | Sender | Creates the business document in their ERP or accounting system |
| 2 | Sender’s Access Point | Validates and sends the document into the Peppol network |
| 3 | Receiver’s Access Point | Receiver’s Access Point receives the document from the network |
| 4 | Receiver | The receiver gets the document in their own system in a ready-to-use format |
While the 4-Corner Model is the standard Peppol flow, some countries and industries have added an extra step to meet local requirements. This is where the 5-Corner Model comes in. It works in much the same way but with one additional “corner” in the process, which can change how documents are routed through the network.
Peppol 5-Corner Model (Peppol CTC)
The Peppol 5-Corner Model, also referred to as the Peppol CTC (Continuous Transaction Controls) model, builds on the standard 4-corner Peppol flow but adds an extra step in the form of a government platform.
In this model, invoices are not sent directly from the sender’s Access Point to the receiver’s Access Point. Instead, they must first pass through a government platform where the document is validated, approved, and registered before it can continue through the Peppol network.
This approach is used in countries, as France, that require near real-time validation of invoices by tax authorities. Because the government becomes part of the transaction flow, the process expands from four to five participants.
What is Peppol CTC?
Peppol CTC refers to the use of the Peppol network together with Continuous Transaction Controls. In this setup, Peppol provides the infrastructure for exchanging invoices, while a government platform performs validation or reporting as part of the transaction process.
The exact implementation can vary between countries and may include additional requirements such as specific formats, archiving rules, or data reporting. This can make it more complex for companies to ensure that their e-invoicing processes remain fully compliant.
| Corner | Role | What happens here |
| 1 | Sender (You) | Creates the business document in their ERP or accounting system |
| 2 | Sender’s Access Point | Validates and sends the document into the Peppol network |
| 3 | Government Platform | Validates, approves and registers the document |
| 4 | Receiver’s Access Point | Receiver’s Access Point receives the document from the network |
| 5 | Receiver | The receiver gets the document in their own system in a ready-to-use format |
Final thoughts about the Peppol 4-Corner and 5-Corner Models
Both the Peppol 4-Corner model and the Peppol 5-Corner Model are becoming increasingly common, used not only across Europe but also in other regions adopting Peppol for e-invoicing and document exchange.
No matter which model your business needs to follow, working with a certified Peppol Access Point ensures that your documents move smoothly and securely from sender to receiver.
If you want to learn more about how Peppol works and what it means for your business, check out our other blog, The Complete Guide to Peppol. And of course, feel free to contact us if you need help setting up or managing your Peppol flows.
Why countries are adopting Peppol CTC
Many countries already use Peppol for B2G (Business-to-Government) invoicing. Because the network is already widely adopted and standardised, it has become a natural foundation for expanding into B2B and CTC frameworks.
As a result, we are now seeing more countries adopting Peppol-based CTC models as part of their e-invoicing mandates.
How TrueCommerce supports Peppol and CTC
Whether you operate in a country using the traditional Peppol 4-Corner Model or a Peppol CTC 5-Corner Model, working with a certified provider is essential.
As a Peppol-certified Access Point, TrueCommerce helps businesses send and receive electronic documents through the Peppol network in the correct format and according to local regulations.
This ensures your invoicing processes remain compliant as global e-invoicing regulations continue to evolve.