Greece clearance model e-invoicing: How does it differ from Belgium’s Peppol approach?

Two countries, two mandatory e-invoicing systems, two fundamentally different architectures. Greece and Belgium both launched B2B e-invoicing obligations in early 2026 — but the similarities end there. Greece opted for a centralised clearance model via the government platform myDATA; Belgium implemented the Peppol standard based on the decentralised 4-corner model. For businesses active in both countries, this means two separate compliance trajectories, two different technical integrations, and two sets of rules.

But caution is warranted: plans and practice diverge in both countries. This article explains not just the architectural differences, but also the actual implementation status — so you know exactly where things stand in February 2026.

The current state of play: ambition vs. reality

Belgium: 4-corner live, 5-corner is a plan for 2028

From 1 January 2026, e-invoicing via Peppol is mandatory for all Belgian VAT-liable B2B transactions. The law is in force, over a million businesses have registered on the network, and the obligation to be able to send and receive is real. A three-month tolerance period (until end of March 2026) applies for businesses that are not yet technically ready.

The active model is the classic Peppol 4-corner model: invoice exchange runs directly between businesses via certified Peppol Service Providers (Access Points), without government involvement in the invoice flow. The Belgian tax authority does not currently receive real-time transaction data.

The 5-corner model — where the tax authority joins as a fifth corner receiving real-time reporting data via e-reporting — is a separate, future project. Technical specifications are currently being developed. The intended implementation is 2028, aligned with the ViDA initiative. There is no certified infrastructure, no live system, and no final specifications available yet.

Status overview Belgium:

Greece: clearance model live, but already delayed

Greece had officially set the start date for large businesses (turnover > €1M in 2023) as 2 February 2026. On 17 February 2026 — two weeks after the planned start date — the Ministry of Finance and tax authority AADE officially announced a delay: the obligation for large businesses now begins on 2 March 2026, with a transition period until 3 May 2026.

The clearance model via myDATA is technically operational: EDIP providers are certified, the free AADE applications (timologio, myDATAapp) are available, and the assignment of a MARK identifier after validation works. But practical implementation at businesses is proving more difficult than anticipated, hence the delay.

An important detail missing from much coverage: the clearance model validates invoice data and assigns a MARK identifier, but does not regulate how the invoice is subsequently delivered to the customer. In practice, after clearance, a PDF with a QR code is often still sent. The digital delivery step is unregulated — a fundamental difference from the Peppol network, which standardises the entire exchange infrastructure.

Status overview Greece:

The Greek clearance model: how does it work?

The core of the Greek system is the myDATA platform (my Digital Accounting and Tax Application), operational as a reporting platform since 2021. In the clearance model: before an invoice is legally valid, the invoice data must be submitted to myDATA. After validation, the invoice receives a unique identifier (MARK) and a QR code. Only then may the invoice be sent to the customer.

This gives the Greek tax authority AADE maximum control: every transaction is visible before money changes hands. VAT fraud is detected in real-time through automatic linking of invoice data to VAT returns. It follows the same principle as Italy’s SDI system and Poland’s KSeF.

What distinguishes the model from Peppol: after clearance, delivery to the customer is technically unregulated. The system ensures VAT compliance but not standardised digital exchange. After validation, the invoice can be delivered via email, PDF, or even paper — as long as the MARK identifier is included.

Is the Greek B2B system actually e-invoicing?

This question is rarely asked, but it matters. The European definition of e-invoicing — under Directive 2014/55/EU and standard EN 16931 — describes a structured, machine-readable document (XML, UBL or UN/CEFACT CII) that is legally exchanged between supplier and customer and can be automatically processed by the recipient’s system.

Measured against that definition, the Greek B2B system is in practice not e-invoicing — it is mandatory fiscal data reporting with a validation stamp.

What goes to myDATA: not a UBL invoice

What a business submits to myDATA is not an EN 16931-compliant invoice, but a ‘synopsis’: a summary of invoice data in AADE’s own JSON/XML schema, transmitted via REST API. This schema contains Greek tax classifications (document type codes such as ‘1.1’ for a standard sales invoice, income and expense categories) that do not appear on the invoice sent to the customer. It is reporting data for the tax authority, not the legal invoice document.

What the customer receives: a PDF with QR code

After MARK validation, delivery to the customer is unregulated. In practice, the customer receives a PDF with a QR code linking to the myDATA record. That is not a structured file that an ERP can automatically process. The recipient still needs to key in invoice data manually or via OCR — precisely what e-invoicing is designed to eliminate.

The technical specifications for what format the B2B invoice file itself must take — the document exchanged between businesses — have not yet been officially published by the Greek authorities.

B2G is different: that is genuine e-invoicing

The B2G route in Greece works fundamentally differently. Invoices to the government are cleared via myDATA and then delivered as Peppol BIS Billing 3.0 files (UBL or CII, fully EN 16931-compliant) via the Peppol network. The government entity receives a structured XML document that its systems can process automatically. That is e-invoicing in the technical sense of the word.

The conclusion: two systems, two definitions

For B2G, Greece does genuine e-invoicing (Peppol + EN 16931 XML). For B2B, Greece does mandatory fiscal data reporting (AADE JSON/XML synopsis to myDATA) followed by unregulated PDF delivery to the customer. The term ‘e-invoicing’ that the Greek government uses for its B2B mandate is legally defensible — the law does require invoices to be issued in electronic format — but it describes something fundamentally different from what Belgium, Germany or the EU-wide ViDA directive mean.

For businesses active in both countries, this is more than semantics: your Belgian ERP connection can automatically process Peppol BIS Billing 3.0 files. Your Greek ‘e-invoices’ still require manual processing or a separate OCR step in practice — unless your EDIP provider offers additional services for structured delivery.

The Belgian Peppol 4-corner model: how does it work?

Belgium implemented mandatory B2B e-invoicing from 1 January 2026 via the Peppol network, based on the classic 4-corner model. This is a decentralised approach in which the government plays no direct role in the invoice flow.

Invoice exchange runs via certified Peppol Service Providers: the sender transmits via their Access Point (Corner 2), the Peppol network routes the invoice to the recipient’s Access Point (Corner 3), which delivers the invoice to the buyer (Corner 4). There is no central government gateway. The tax authority receives no real-time data — that is planned for 2028 via a separate e-reporting project.

The difference from a clearance model: the invoice exchange itself is fully standardised end-to-end. Not a PDF-with-QR as the end product, but a structured machine-readable invoice arriving directly in the recipient’s system.

Key differences at a glance

The Peppol split in Greece: B2G vs. B2B

Greece has a notable distinction. For B2G invoices (to the government), Peppol is already mandatory: invoices are cleared via myDATA and then delivered via the Peppol network, handled by the National Interoperability Centre (KE.D). This model combines clearance and standardised network delivery.

For B2B transactions, a different regime applies: clearance via myDATA, but no regulated network delivery afterwards. Businesses that supply both the government and other businesses in Greece must manage two parallel processes — even within the same country.

Greece and ViDA: stronger than it looks, but not without tension

It is too simple to say that Greece’s clearance model is ‘poorly aligned’ with ViDA. The reality is more nuanced, and for Peppol.now it is important to be precise.

Where Greece is genuinely strong

On the data and reporting dimension of ViDA, Greece is ahead of most EU member states. myDATA already delivers what ViDA aims for: real-time transaction-level reporting, a fully digital audit trail for VAT control, and operational experience processing millions of invoice records per day. Most other member states still need to build that infrastructure and experience.

Where it structurally diverges

The tension with ViDA is not in the data layer, but in the exchange architecture. ViDA treats the e-invoice as a legal document exchanged between businesses — with the government receiving transaction data as a derived stream. In the Greek model, the invoice is primarily a reporting object to the tax authority; delivery to the customer is a second, unregulated step. That is a fundamentally different orientation.

Concretely: ViDA requires interoperability for intra-EU transactions via standardised networks (Peppol or equivalent), with EN 16931 as the semantic foundation. The myDATA system is nationally oriented, not built for cross-border exchange. Greece needs a separate Peppol layer for that — which already exists for B2G, but is absent for B2B.

The conclusion is not that myDATA is ‘wrong’ — for national VAT enforcement it is effective. But the system does not replace an EU e-invoice. It lives alongside it. That means Greece will likely need a second adjustment for the ViDA transition (2030–2035) to standardise the exchange layer as well, while the data layer is already in order.

Belgium is architecturally better positioned for that exchange layer: the planned 5-corner e-reporting in 2028 is a logical extension of the existing Peppol network, not a replacement. But on data maturity and compliance experience, Greece has a head start that should not be underestimated.

What does this mean for businesses active in both countries?

1. Two technical integrations

For Greece, you need a certified EDIP provider integrating with myDATA. For Belgium, you need a certified Peppol Service Provider. These are two separate connections with fundamentally different architectures.

2. No invoice interoperability between the countries

Your Peppol connection for Belgium does not work for Greek B2B invoices. Conversely, your myDATA connection does not work for Belgian invoices. Businesses hoping to serve both markets with a single solution will be disappointed.

3. Foreign suppliers: off the hook, but not without consequences

Foreign businesses without an establishment in Greece are not obliged to send e-invoices under Greek rules — even with a Greek VAT registration. The same applies to Belgium. But your Greek and Belgian customers must maintain two parallel systems: standardised e-invoices from local suppliers, plus traditional invoices from international partners. This creates administrative pressure on the receiving side that can affect the business relationship.

Frequently Asked Questions

Does Belgium use the 5-corner model?

Not yet. The current Belgian system is the classic Peppol 4-corner model without direct government participation in the invoice flow. The 5-corner model (where the tax authority receives real-time transaction data via e-reporting) is a planned follow-up project with an intended implementation in 2028. Technical specifications are still being developed.

Is Greek e-invoicing already live?

Technically yes: the myDATA clearance system is operational and EDIP providers are certified. But the obligation for large businesses has been delayed from 2 February to 2 March 2026, with a transition period until 3 May 2026. Many businesses are currently in a parallel-use phase.

Can I use my Belgian Peppol connection for Greek B2B invoices?

No. Greek B2B invoices require clearance via myDATA through a certified EDIP provider — a different system from the Peppol network. Your Peppol connection is usable for B2G invoices to the Greek government, which runs through both clearance and Peppol.

Is the Greek B2B system actually e-invoicing under the European definition?

Not really, for B2B. What is submitted to myDATA is not an EN 16931-compliant UBL/CII invoice but a fiscal data summary in AADE’s own schema. What the customer receives in practice is a PDF with QR code — not a machine-readable structured file. For B2G (invoices to the government), it is genuine e-invoicing: Peppol BIS Billing 3.0 is used there.

Which model is more future-proof?

It depends on the dimension. On data maturity and compliance experience, Greece is strong: real-time transaction-level reporting and a proven audit infrastructure are exactly what ViDA requires. On exchange architecture and EU interoperability, Belgium is stronger: the Peppol 4-corner model is EU-interoperable and architecturally ready for the 5-corner extension in 2028. Greece will likely need an additional adjustment for the exchange layer; the data layer is already in place.

Sources

• AADE / Greek Ministry of Finance — official delay announcement 17 February 2026: https://www.aade.gr

• vatcalc.com — current status Greek e-invoicing mandate: https://www.vatcalc.com/greece/greece-mydata-e-book-and-e-invoices-update/

• cleartax.com/be — The Peppol 5-corner model: from Belgian e-invoicing to e-reporting: https://www.cleartax.com/be/nl/belgium-peppol-5-corner-model

• vatcalc.com — Belgium 4-corner 2026, 5-corner 2028: https://www.vatcalc.com/belgium/belgium-b2b-e-invoicing-july-2024-update/

• The Invoicing Hub — Greece compliance: https://www.theinvoicinghub.com/einvoicing-compliance-greece/

• Peppol.now — European e-invoicing model overview: https://peppol.nu

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